I have wanted to add my two cents to the catcall discussion (Beyond Parody: How Feminists Are Redefining 'Hello' As Sexual Assault).
Let's first accept that men, especially young men, tend to be hormonally sexually alert and curious most of the time. Flirtatious too, when feeling confident. Doesn't that mean that the catcalls and other uninvited words simply come down to a matter of manners?
Here's a related question:
A good and mannerly young fellow on the subway finds himself standing next to a young lady who is reading Jane Austen. Cupid's arrow strikes him. From her appearance, her movements, etc. he feels that this is the girl God has made him for and he can't keep his eyes off her.
Should he say "How do you like the book?" Or should he decide not to be taken as a creep, let it pass, and kick himself for a month for passing up what might have been a life-changing opportunity to meet the woman of his dreams?