If the micromort was sold as an expected number of deaths, then I wouldn't have as much of a problem with it. (My major problem is that you can't die more than once, so probability seems to be more of a concern than expected number.) The article calls it "a one-in-a-million chance of dying", though.

For example, playing Russian Roulette once is about 166667 micromorts. Playing it 6 times is 1 mort of risk, but the probability of dying after 6 plays is not 1. (It's 1 - (5/6)6, or about 2/3.)