Narcissist, looking for female attention and insecure as he'll clearly be fishing for compliments and verification that he is 'good looking'. So yeah I'd say it's a worry, same as guys (with self respect) not wanting to date girls with their tits or ass hanging out.
Some just like to show off me for example didn't have much choice for my reality check thing my gym picture was the only decent picture I had otherwise I would have used one with my shirt and stuff on.
I see many guys in "no shirt pix", even in magazines and---yes, dating sites as well, sweetie. Might I suggest, that if she is one bit worried about "shirtless sonny," she should think about having a face to face on Skype and or Yahoo. It's not only a good way to get to know one another but---"it is a good way to know what one looks like "from head to toe.":))xx