Huge bankroll is infinite. You will lose in the long run no matter what. Varience ensures that you don't get the same amount of win and loses, you will eventually hit a very long streak and there goes your bankroll. Also, the house edge decreases your likelyhood of winning.
You will not necessarily eventually hit a very long streak. Progressive systems tell you when to stop, and it is far, far more likely that you will stop before you hit such a long streak.
Progressive systems are bad enough without having to misrepresent the one thing that is actually good about them. The one good thing about progressive betting systems is that you are much more likely to make a profit than suffer a loss.