No...? Don't most bets (whether casino or sports bets) have a limit on the amount of bet? There might be some special cases, but they're called "special" for a reason and isn't exactly a regular part of the system. Not sure though, never really bothered trying it myself after all.

As for the second, casino lotteries should have big prize pools but probably not as big as national lotteries. they're the only ones afaik that cater to such big amounts of prize pools in terms of lottery. But I reckon you'd probably have higher chances in the former since it has less participants than the latter.