@Spanners – so I repeat, I’m not defending this particular case, I can’t say what happened, but I do agree it looks very dodgy. But I am playing devil’s advocate when I say, I wouldn’t say it’s impossible for the ball to do what it did, but that’s just my opinion.
The safeguards are the RTP. For European roulette this is 97.3% (2.7% house edge). Over a long period of time, this is enough for any casino to assure themselves a profit.
That being said, there could always be a small casino with a high table limit but low average bet sizing from the players. If someone was to come in on a single visit, bet big and win, then never come back, that could cause problems for the casino. But that is a very specific scenario and the safeguards the casino has in place should be around the table limits in that situation.