Poker is just a game where chips are used to keep score. People can wager real money on backgammon, chess, gin rummy, sports, monopoly, pooh sticks or just about anything where the outcome is unknown. Handling one's money well (i.e. bankroll management) is completely different from learning to play a particular game. As for gambling on a game that you don't play well, I think Dirty Harry said it best:
"A man's got to know his limitations"
I have two boy's, 9 and 6 who are already learning to play chess and poker among other games. They get an allowance to help them learn about saving and delayed gratification, and eventually I plan to teach them about handling their money in other situations because I don't want to just send them out in the world trying to figure these things out for themselves. My general philosophy is that the sooner you start learning something, the better you are likely to be at it.