I used to play friut machines as a teenager then went into horse racing in my 20`s all for small stakes, now im into my late 30`s i still gamble on the horses. i use betfair myself but the percentages alot better than fruities, i dont make my gambling pay, but i find it excellent value for money, my minimum stake is £2 and have lost £150 over 5 years (online account).
To answer the question though i gamble to prove my thoeries/selections right, obviously i lose more than i win, but the is nothing better than proving yourself right with 10/1 winner.