Why do lesbians enjoy watching gay porn?

i know that women like watching gay porn (two guys), but why do lesbians like watching gay porn? ive seen alot of articles on the net saying this. can some girls please explain?

and why isnt it true the other way, gay men dont watch lesbian porn, in fact they are repulsed by it???
Update: found some articles:

http://www.lesbilicious.co.uk/community/why-do-lesbians-love-gay-man-porn/

http://www.metro.co.uk/metrosexual/article.html?Women_who_like_to_watch_gay_porn&in_article_id=356386&in_page_id=8&in_a_source=&expand=true
16 answers 16