The point of a rollover clause on bonus offers works for both sides of the wager. Sportsbooks will always put rollover clauses on bonuses to prevent people from depositing, getting the bonus and then withdrawing it all.  The rollover states you must play the entire balance at least once and usually multiple times.  If a company offers you a 20% bonus with a 3X rollover: Let's say you deposit $100. They will give you $20 for your bonus, but you must risk a total of $300 (3 times your deposit) before you can withdraw any of that balance.

The darker side of this deal is that the sportsbook operators know that the more you risk your money the more chances you can lose it. This is why you see these ridiculous rollovers attached to great bonuses. ex. "100% bonus on deposit up to $500, 10X rollover". That is one I saw recently. 10X rollover!  That type of clause will keep a conservative like me at bay for a year.