The kids each got a chance to play "the claw" game at the bowling alley when we were there this week.  Neither of them won anything and I didn't hand out more money to keep trying.
The Tumbleweed came to me this morning with $6 in quarters and asked how many turns she would get.  We talked it through and determined that since it costs 50¢/play she would get 12 plays.  Her response, "Ooh yay!  When can we go?"
To that I said, "Honey, even with 12 plays you still might not win anything at all and then you won't have any money left.  Wouldn't you rather take your $6 to the store and buy something?"  
Her answer, "But mom, I could win 6, or even 12, prizes.  I can't get that if I just go to the store."   And she bounced off to the other room.
Oh well, I tried.  We will have to revisit the discussion the next time we go bowling...