Surely it's just being polite. Most women probably appreciate being complimented anyway.

This is the view of many men who have responded to that video of that woman who recorded all the catcalls she received while walking around NYC for 10 hours http://www.vox.com/xpress/2014/10/28/7084995/a-woman-walked-around-new-york-city-for-10-hours-and-filmed-every

Come on men, let's try and put a stop to all this yeah.