Your odds of hitting on Red or Black is not 50/50. It is 47.37%. The ball can land on green. If you don't get your money back, it's a loss.

http://wizardofodds.com/roulette

Most games at Casinos are stacked against you. They have very smart math and stats geeks who've figured all this out. Try counting by yourself with a 6 deck shoe. Or even a single deck is hard because they reshuffle after 2-3 hands.

One interesting thing from the article. Picking unpopular combinations of numbers can offer less competition in large jackpots. i.e. adjacent numbers 23-24-25, etc... because people mistakenly believe that's less likey to happen than totally random numbers.