[ Fashion & Accessories ] Open Question : Why do college girls slip off their shoes and go barefoot when they study?

I just find it weird how they go barefoot at a college library but not at another public place like Starbucks. I think it's sexy when a hot, long-legged blonde girl slips off her flip flops and rests her bare feet and legs on the foot rest in front of me with her soles exposed. Sometimes, I'll sit in the couch right across from them when they do this and they'll smile at me when they notice me looking at their feet. Is there a reason why they feel so comfortable going barefoot at school libraries? Isn't it embarrassing?