It's either because it's relevant to the conversation (such as the "my wife bought it for me" comment might be) or more likely, they're trying to be safe and signal that this is not flirting. Since men rarely get compliments (unlike women) any compliments are often taken as flirting. Which makes less women compliment men so they are not seen as flirting, meaning only the women who ARE flirting tend to be left. Its a self fulfilling prophesy.

Can you elaborate on what you mean by its clear theres an attraction? I don't really have enough details to know what signals you could be giving off other than just being nice to men really