Not all guys are like this at all. I'm not, for one. If I liked a girl I told her (and more often than not found that they weren't interested!

), but some guys just don't see it like that. My best friend when I was at school was one of those people and it was the one thing I loathed about him. Some would see it as jealousy because he was a model who could attract a smile from almost any girl he chose but I can put my hand on my heart and say it wasn't.
I think its rather a harsh generalisation to make as it is most definitely not true about ALL guys - even though it may seem it is. Maybe you've just had bad luck so far.
In fact, some would say its more true about women (but 99% of those are men!

)