Without advance deposit wagering?
I see Youbet is now offering a 10% winners bonus on the Saratoga late pick 4. So if it pays $1000 and you hit it, you get back $1100 (an extra $100 that you will rebet of course). In addition, they have some sort of $20 free bet deal. These types of promos are seen at several ADW's out there; I am just mentioning Youbet because I saw it in my email today.
I suspect that without ADW - reselling and adding to churn with rebates - we would be below $12B this year in handles (much lower than that if we counted the large rebate shops of course). There were rumblings this past two years (before the bottom fell out of handles) that horsemen groups and some industry insiders wanted to run and take over advance deposit wagering. My goodness, we can thank our lucky stars that never happened. The chances of getting a 10% winners bonus, or free bets with those folks running wagering would be about equal to hitting back to back to back pick 6's.