Sometimes dumbass cashiers scan a ticket and don't cash out for some reason and don't check to make sure that the ticket is not left in the paid status. The ticket holder goes to the next store and it registers paid. A lady made the news in my city when she had to go to the lottery commission to have it straighten out just because a dumbass cashier didn't do her job right. It took her months to get paid.
Sure we have crooks but everybody ain't dishonest when a ticket shows paid. In case you weren't clear on that.