And yes, it is a risk, even if your mask is solid. There's always the risk that the lottery commission could say "oh, come on, the terms and conditions prohibit this kind of thing", leading to a protracted legal battle.
Not sure why this is down-voted. It's spot on.
On the legal topic, I think it’s not a prohibitive risk. It’s completely in the game’s design and completely within the lottery’s control as they basically control distribution. Running a casino isn’t a risk free operation, miscalculations cost money.
They bought tickets and won due to the inherent probability of the game, fair and square. No inside information, no gaming of anything.
What supposed to make mass ticket buying non-profitable is the expected return being < 1, not any hidden terms and conditions.