According to the Kelly criterion, yes they should be. You need to me risking that much to maximum the expected log of your bankroll. If you only risk 1% of your bankroll on the highest payout, you're risking much less than 1% of your bankroll on the other payouts, and those are the most common. The big payouts are rare enough that apparently it's worth risking more than 1% and relying on the fact that they don't come up very often.