Only desepered players would be moving from football to roulette.
I think you meant desperate and not really desperate people would bet on roulette because actually sports has higher house edge and winning on sports is more difficult than as compared to casino with a 1-2% of house edge.
Sometimes i thought iRoulette is only made for wealthy persons who don't really care if they lost all the bets .
Roulette is not different than all other games and basically each game has a different version of winning but the theory remains the same that you are betting against a constant house edge so it needs luck to win and hard to maintain that luck in long run. I myself do not like roulette but it is fun to watch the wheel spin and have a number popped up and has a different thrill when compared to other games.