[dmurray]

Depends if it's total amount wagered or total amount lost.

If amount wagered, at typical takes for bookies/casinos/lotteries that would mean people would lose in expectation 0.1% to 5% of their income. Seems like a reasonable compromise that people could indulge in gambling for entertainment but very few people would be caused financial problems. With some weird second-order effects, but no regulation is perfect.