To be sure, what Riker said was that "they" (apparently including all the people he knew and respected) no longer enslaved animals for "food purposes".
Perhaps other purposes of slavery are fine, but slavery for the purpose of eventually being eaten is considered too gruesome? Certainly it would be impossible to collectively condemn all forms of slavery - or else Riker would have to cease being slave to Starfleet, or to his nasty habit of breathing air.
Of course, Riker himself is an avid killer of fish for food purposes. But there's no element of slavery there if he fishes free and wild little swimmers from Alaskan rivers.
Timo Saloniemi
Perhaps other purposes of slavery are fine, but slavery for the purpose of eventually being eaten is considered too gruesome? Certainly it would be impossible to collectively condemn all forms of slavery - or else Riker would have to cease being slave to Starfleet, or to his nasty habit of breathing air.
Of course, Riker himself is an avid killer of fish for food purposes. But there's no element of slavery there if he fishes free and wild little swimmers from Alaskan rivers.
Timo Saloniemi