Perhaps people just need better hobbies. ;) Really, though, I think some people feel better about themselves when they are degrading others. Also, there are some who get tricked once and so think that everybody tricks people on the internet. I guess it is a touch of paranoia for some.
It's tough enough to gather up enough courage to put up an ad on a dating site when it feels like becoming just another slice of the meat market. There are people on this site that make fun of others for their longing to be together with someone and also that do not value their efforts to find friends.
Moreover a lot of people have the prejudiced idea that if you have to put up an ad to find friends or a partner, there must obviously be something wrong with you.
It's true that people can make wrong claims easily when they are hiding behind the internet but too many people think that absolutely everyone that puts up an ad has something to hide or some ghastly reason why they can't find friends or a partner without an ad. It's just simply not true because there isn't a place on every corner made for people to get to know one another without getting drunk, without paying some price for being part of some club or generally wasting money and not even knowing whether those other people really want to get to know one another and also not knowing if they are even worth getting to know.
The biased thinking that everyone lies about their age, their beauty, their money, seems to be common place. There are even sites on the internet that interpret ads in a negative manner to show people what they might end up with if they take ads at face value.
Are we really all liars or have a lot of people missed the fact that there are liars and honest people everywhere including the internet?