Now if you take a more conservative strategy, lets say you can lose 1% or win 35% of your initial bankroll, sure it may take longer but if you have an edge in your favor it should take a very unlucky streak of bad luck to go bankrupt and when you win your winnings will compound on top of eachother and the casino still will go bankrupt within a month if they don't ban you from playing roulette. So a more conservative strategy nets you more cash on average.
This is kind of a tangent, honestly I'm not even sure how unlikely it is for a gambler with a reasonably executed winning strategy to double up a few times over a long night if they're running hot. They would be doing this over hundreds of rounds of betting, so a small edge compounds rather quickly.
A mathematician with a clue and a winning house edge would bet fairly conservatively and bet more as their bankroll expanded and bet less as their bankroll retracted to reduce their risk of ruin. Somebody making 50x their bet in an hour at roulette may sound impressive to many people, but it's obviously idiotic to any gambler worth their salt. It's so unlikely that it suggests incompetence at risk management more than it does genius gambling.