Why is there so much 'reality tv' program?

yes i do like reality shows ,because we come to know how real are these celebrities apart from they reel life..........as we can know about they nature,colors,of they persnality.....how they are in real..aprt from they socailwork they do for people. it comes to know how they can cope up being with people who they dont know etc... i personally like BIGBOSS WHICH HAD started in the month october.........its really a reality show.......good timepaa also.....

I like American idol but other then that I like movies and maybe 7th heaven and house.