I still don't understand how you're interpreting the environment argument as a "choice".

I don't think people "choose" to be gay, but I also don't think it's necessarily something you're born with. I think it's something acquired, but not consciously.

A person's interests and beliefs are a result of their upbringing, based on how their parents/friends/teachers influence them(positively or negatively). If a certain taste has no factor in a person's childhood(or teenhood) either way, they probably won't acquire it.