Just to speak on the actual matter, while this discussion is at a fever pitch right now, I don't really foresee this being a chronic issue, now that opinions have been aired, so again any actual mechanical solutions are probably not necessary.
The biggest problem here has been the rapidly shifting culture as the user base grows; older users largely are in the Discord community because the site was much smaller when first publicly open, and have had more time to form a sense of community around their chickens, ergo are typically more attached and/or were already more familiar with one another. There were also far fewer chickens, so each individual chicken felt more valuable.
As the user base grows, and people not from the same initial circles join, they are unaware of any of that culture. Newer users also were not present for when circulation of chickens was much more difficult, so people used the Farmhouse also as a means of distributing cheaper chickens specifically for/to those who were -not- in the Discord, rather than as an actually impartial market. So there's a cultural/context clash between two user groups who are coming at the site in two different ways, and neither is specifically at fault, nor should be faulted for feeling hurt on the matter.
The real fact of the matter is the site has only been open for 4 months, so while a big rift like this can feel a little apocalyptic, it's really just going to have to iron itself out over time. Something like an unofficial, user-compiled community etiquette guide might do the trick so that the community can regulate itself, and new users can get a quicker feel for the culture. This would (hopefully) also eliminate the need for users to have to put warnings in their listing descriptions, which just isn't fun to have to do for either side. (I'm a bit busy with work atm but I'd be willing to help compile a guide like this when there's time, if anyone wants to share suggestions.)
My only opinions regarding the actual flipping itself are: If it's a chicken off the farmhouse and you're release-flipping it for a profit of 10 eggs or less... it mostly seems wasteful; someone else might have wanted that chicken and with a little patience there's many other ways to get that amount of eggs. If it is a -gifted- chicken, that is where things get hurtful, since like was mentioned here previously, that's like someone giving you a gift and you sell it the next day; not illegal, but generally against the social contract and considered hurtful. Basically, no matter how you feel about the individual chickens it's just symbolically rude aha. The best way to make a profit without potentially harming others is to simply breed your own chickens for release, if that's your game; it's not an instant solution, but it's a steady one.
But again, at least as far as the farmhouse situation, this, I think will work itself out as people decide how they want to utilize the resources in the way best suited to them and the site has more time to find some equilibrium.