My sons, both of whom are in their 20's, have recently discovered poker. Since they were raised in a non-gambling home (I have never even bought a lottery ticket), this astounds me.
More and more young people are now gambling and it generally starts innocently and in subtle ways. It is becoming socially acceptable to participate in 50-50 draws, casino nights, and afternoon poker games.
While most teens start to gamble just "for fun," some will end up with a serious gambling problem and it can easily become an addictive pastime.