I guess the difference is not in the transaction itself. The key part is that insurance counteracts a risk on your part: If it lowers the variance of your final balance, it's insurance. If it raises the variance, it's gambling.

When I was at Microsoft about 15-16 years ago there was a fairly big poker setup. Where I was, and I'm sure across the board, the advice that was given was that we were free to have tournaments on company property, however, one of the rules were that you could never actively bet truly blind, i.e. you had to see your cards first. According to whomever decided that, that was sufficient to keep your poker game a game of skill, and not gambling, since if you didn't know your hand, you were just relying on luck, not playing odds.

Well, that line mostly boils down to whether the expected value of the bet is positive, and the insurer in the article seems to do pretty sound analysis to ensure his expected return is positive. I don't see where it gets close to gambling.

There's no difference between an actuary working at State Farm and a sports bookmaker at Caesar's. Except for the pari-mutuel aspect.