Combine 1) the competitiveness that men are socialized with in athletics with 2) the dynamic that both straight women and gay men have to attract men based on physical appearance and 3) add in the emotional stuntedness of a closeted youth and of course you get shallow- catty terrible behavior. This is why at dance parties you first find all the (usually) tall (usually) white guys more interested in posing and being seen… and then go dance with everyone else and have a fantastic time. Cop an aggro-alpha attitude if you want- but if you can't laugh at yourself you're just another asshole.
Having lived in New York for nearly 13 years- I've found that not much has changed for me as far as bullying goes. Bullying within the gay community is very rarely discussed- but gay people are really mean to each other sometimes.