It doesn't only bother me practically. Yes I did consider the fact that they'd have to compete, though I didn't consider the fact that they evolve all the time anyway, that's a good point. BUT, especially if they're talking about something as drastic as eating up a significant amount of carbon in the air, it will change the ecosystem. It'll pose the same danger as moving animals across continents.

But really it bothers me in a different way. I'll say morally, for a severe lack of better term. Maybe existentially. It doesn't sit right with me that we'll be living amongst creatures created in a lab, and that there's no way to differentiate them. I don't believe in God, but I like that we exist within a certain biological framework, it just feels like part of our identity. That the players are allowed to change the rules bothers me.