You probably just meet pricks. There are lots of great guys out there, but equally there are lots of pricks... but then the same applies to girls too. Meeting the nice ones while avoiding the evil bitches of satan is a skill.
Why are you more likely to meet pricks? Pricks typically have more self-confidence and are self-assured, particularly around women, and most "nice" guys do not have much self-confidence and are, as such, more ellusive and difficult to meet and are probably sitting at home on the internet somewhere wondering why every girl they meet is a prick...