I have a feeling this a shit post, but on the off chance it isn’t, people only respond like that when someone has acted like a creep or pushes the issue to an uncomfortable point. Put simply, not every woman you meet is going to be comfortable enough to send pics and, in healthy, plutonic relationships they should never even be expected to. A genuine friendship is worth more than that.
Still, while those sorts of picture arrangements do occur occasionally, they happen naturally with the development of a relationship and, at best, are a bonus to the underlying connection. Treat women with respect, appeal to their emotions, and form a genuine connections — those aspects of any relationship are far more rewarding in the long run. Women are pretty awesome.
Also, those pushy expectations are precisely why foot fetishists have such a creepy reputation.