As part of their effort to hook tens of millions of Americans on gambling, sportsbooks have spent billions of dollars on splashy bait. They flooded last season’s NFL broadcasts with commercials. Caesars transformed a fleet of Ubers in Arizona to look like chariots. BetMGM claimed to have received the first bet placed from space — relayed from a SpaceX shuttle to a proxy in Las Vegas.

In the fight for sports bettors, astronomical spending — from those incessant broadcast ads to enticing sign-up deals — is part of a considered gamble, based on projections indicating that sportsbooks will clear several thousand dollars over the lifetime of their average customer.