The chosing of words here:
a lay follower should not engage
in five types of business is very conductive and wise.
"Engage" -> three doors of conduct, mental, by signs or direct by body.
When ever you may get the feeling to engage, to be involved, to feel not well with it, try to change and fix it. It's in most cases not really possible to generalize useful for many in certain details, but the main objectives are to find freedom from remorse by keeping precepts and once they grow to a matter of heart and leave the level of outwardly "rituals" or justification of all variants, the wise and conductive way is to follow ones heart and uprightness. Whether such is made by changing whole things or by changing ones also executed level of engagement in a non-denying way, a non-hypocratical but honest way, might be also different case by case.
At least, once aware and clear of effects, mental approve, not to speak of enjoying benefit based on suffering of others, althought not ordered by signs or words, not done bodily and direct, such mental kamma has effects.
That is why it is suggests but not often forwarded, since difficult from most, or certain "dangerous" to lose persons favors: "a lay follower should not engage in five types of business".
Especially in SE-Asia it is very seldom straight and un-flowered forwarded.
Maybe a sample is useful to make it more alive: There is a young family making their live by selling pork is soup and the householder drives daily his motorbike through the villages to sell "fresh" meat from pigs. They usually love giving and when ever on alms coming till their village, not only meeting the husband on his hurry selling drive, they would joyfully offer some of the noodle soup. It has needed a very long time till my person was able to "give a little back", to meet the proper occasion so that they would be able to listen, propably understand. Some days ago the mother of the pair was visiting, and while joyful prepearing alms was moaning on and on "Ohh, steedy ill... permanent sick..." After the round after the meal, the house was crossed again and turning now around, asking "who is permanent sick" my person was explained that the young householder was subject - not much wondering - and got invited to sit down and possible help. So they have been carefully been taught about the issue of livelihood and the protection of silas in regard of sickness and livespan. Not surprising the couple would have prevered to hear a blessing or what ever "miracle" and not much of joy to hear that, yet nevertheless listening... My person had not met the meat driver since this day and did not came till their house since this occation. May it not only be a "the Dhamma is right" but also have possible turned to a longtime better.
One needs to know and understand that sure 40% and more people are actually engaged in meat - or animal trade business and the rest of 55%in other un-lucky trade. Why should the reallity in the west or modern world be much different? Only because the whole way from killing till the serving of food is more defuse and not so easy traceable does not mean that "reality" and less care, or not seeing an alternative, not able to let go of certain things, needed to let go, are not different even more worse.
While people observe things here in the neigborhood here, "reality" enters the homes over there via TV, youtube or SE... who's today not merely just an employee rather than business owner... who is informed and aware, free to choose his ways or not.
What about all the modern occupations and harmful trades, deriving issues?
Step to more remorseless livelihood as soon as issues are traced. There is much more benefit of a seldom to gained live is taking on the "lower" and "simplier", not so material benefical ways to earn a living and to be possible just a servant, house keeper or helper, cleaner... what ever. Its good to be modest and prefer highest Protections:
To have much learning, to be skillful in handicraft, well-trained in discipline, and to be of good speech — this is the greatest blessing.
To support mother and father, to cherish wife and children, and to be engaged in peaceful occupation — this is the greatest blessing.
To be generous in giving, to be righteous in conduct, to help one's relatives, and to be blameless in action — this is the greatest blessing.
There is nothing wrong in being gifted a blessed to be able to accumulate a lot of wealth proper and in rightous earned ways, but it is not wise at all to let go of ones virtue and life at easy for what ever amount of outwardly gain.
"Lesser (of certain things outwardly) is more (peace, happiness and ease).", a prover tells.
Good results require certain hard work: that's the Noble truth of Suffering, and there is just one way out and proper conduct to continue with most possible ease, if still wishing to wander on, take and pay, before or afterwards.
Nearly 24:00 and the sound of hunters gun is to be heared from the near other mountains forests, sometimes just the barking of the deers is the loudest... screeming after a spouse...
Make good use of possible highest blessings gained and give causes so that such effects are not only seeked but gained, as sure as birth is followed by death.
"From an inconceivable beginning comes transmigration. A beginning point is not evident, though beings hindered by ignorance and fettered by craving are transmigrating & wandering on. What do you think, monks? Which is greater, the blood you have shed from having your heads cut off while transmigrating & wandering this long, long time, or the water in the four great oceans?"... The blood you have shed when, being water buffaloes, you had your water buffalo-heads cut off... when, being rams, you had your ram-heads cut off... when, being goats, you had your goat-heads cut off... when, being deer, you had your deer-heads cut off... when, being chickens, you had your chicken-heads cut off... when, being pigs, you had your pig-heads cut off: Long has this been greater than the water in the four great oceans.... "Why is that? From an inconceivable beginning comes transmigration. A beginning point is not evident, though beings hindered by ignorance and fettered by craving are transmigrating & wandering on. Long have you thus experienced stress, experienced pain, experienced loss, swelling the cemeteries — enough to become disenchanted with all fabrications, enough to become dispassionate, enough to be released."
That is what the Blessed One said. Gratified, the monks delighted in the Blessed One's words. And while this explanation was being given, the minds of the thirty monks from Pava — through lack of clinging — were released from fermentations.
[Note: This is a gift of Dhamma and not meant for commercial purpose or other low wordily gains by means of trade and exchange.]