No, its okay to ask guys out, and any guys who offended is not a guy you want to date. But that said I'm talking from a Europian cultural perspective. Not sure in the US. You guys have loads of rules about dating, most of which involve telephones? Never understood it, that and the connection with sport and universities, just strange to me. Sorry I'm blathering.
Regarding you're picture, I didn't know the mighty boosh had made it to the ther side of the fish pond. Old Jack, part man, part fish, part woman, with a man'gina.
yes, the role reversal is uncomfortable for them and as much as they say they like it... they feel like less of a man, it can throw off the whole relationship dynamic. I have asked guys out several times, with initial success but utimately it threw things off, make him feel comfortable enough to do the asking. If he likes you believe me he'll be looking for a hint/excuse to ask you.
If you ask a guy out it gives him all the advantages. Yeah some guys like it because they may be too shy to initiate things with a girl, but if they really like a girl they shouldn't have any problem asking her out. They better ask her out before someone else does. But if you ask a guy out it sends the signal that you are REALLY into him and that can lead to him possibly taking advantage of that. Guys like girls that other people want so if you ask him out that can look like he's your only option.