The words in the title come from People for the Ethical Treatment of Animals (PeTA). I like the words. What they say to me is that the legislators in a country, let's say the USA, do not believe it is wrong to exploit animals otherwise they would have legislated against it and made it illegal.
Some people believe that animal exploitation is immoral but some people don't. If something is immoral it can also become illegal if it is immoral enough and if enough people believe it is immoral.
Clearly not enough people believe that the exploitation of animals is immoral. Indeed, there are lots of questions about what is and what isn't the exploitation of animals. I recently wrote an article about Acro Cats; these are cats trained by a lady to perform circus style tricks and stunts.
Some people will say this is exploitation but a lady commented that she thought it was perfectly acceptable.
With such difference of opinion about exploitation it is impossible for there to be legislation against it because legislation must represent the people as a whole.
Legislation must certainly represent the people and there must be no doubt about it. Sometimes animal exploitation is so obvious and abusive that it becomes animal abuse. Animal abuse, in developed countries, is always legislated against. It is a sliding scale. The exploitation of animals can drift into the abuse of animals which in turn drifts into animal cruelty and ultimately killing.
This sliding scale makes it difficult to define animal exploitation but legislation must always be highly accurate otherwise it becomes unenforceable. If it is difficult to define animal exploitation, it is one more reason why it is not illegal.