If everything comes out exactly right, this can make a case for playing the lottery being better than doing nothing risky but it can't possibly make the case that the lottery isn't massively worse than other forms of gambling. Even if the numbers games are gone going to a casino offers the same opportunity at far better odds and allows you to choose the point on the curve where gambling stops being efficient. I do think however the point that negative-expectation risks can be rational is well taken.