[bryanlarsen]

2 factors:

- you also have to account for the highly likely probability that the jackpot will be split between multiple winners.

- even after that accounting, lotteries do sometimes have an expected value higher than the ticket price. The expected value of purchasing N tickets for the N lotteries that led up to and include the big lottery is still the standard 40-50%, but the N-1 previous paid out much less than expected, so the one with the big jackpot pays out more than expected.