Earning by playing

There are many sites on the internet which are used for earning money.
some of us feel so awkward when it comes to real jobs.Most of us prefer the most simple ways of earning money.
I have reviewed one of the real sites that earn you some money :

I tried this with Gameduels.com and ended up twenty pounds down. First of all i intended to put ten pounds on my account but somehow put twenty on there. When I tried to with draw the ten there was some kind of complication and I had to play through the full twenty so many times over. So I went with it, playing games. The odds are crazily against you. You are matched with people of your apparent level of skill based on how my games you played before and what your score was.
Even if there was a 50/50 chance of winning any particular game tht you play, Your money odds are more like 70/30. So you win one, you’re up, lose one, you’re down lower than where you were before.
This is because gameduel takes their cut of the winning prize – I suppose they have to make a living, but I hope they are happy with my twenty pounds because I will not visit their site any more.
A better business plan would be to offer 50/50 odds, maybe charge a small fee on withdrawal, and make most of their revenue through on site advertising or traffic redirection or something. If they had done tht in the beginning, they would probably have made much more than 20 pounds out of me.
This is a typical example of short sighted business dealing.
The games are fun but not worth paying a continual fee to play. i can get just as fun games to play online for free, except there wont be a chance of winning money.