Hi Jos,
I've though about this a little, and I think you're right about the amount of the bet not affecting the odds. It will not change how many games are won or lost over the long term.
However, being able to vary the amount bet on each round of the game does change the odds about whether a player walks away ahead or behind. That is the main purpose of why the house has a limit; to take that small advantage away from the player.
The limit is usually set low enough, so that it will eventually catch up to a player using the method I described.
Statistics are very accurate over a large population of occurances, if the game is not otherwise rigged, and will always favor the house.
Regards,
LelandJ