This isn't 100% accurate because the stats are to the end of Saturday but 7 days wagering volume was 1,185BTC. That gives 237 million tickets and is a very small part of the 1.1 to 1.2 billion total.
Is the rest mostly botnets or legitimate users or is it too hard to work out.
I guess people can do the 1000 lottery tickets per roll reward and see if they get anywhere...