As far as I know 'no' they are the owners of online casino gambling sites, never gamble, just like the owners of cigarette factories, the owners don't smoke.
The reason: The owner knows the risks and dangers of gambling & also the dangers of smoking, this example is real.

I once asked a person, he used to own a land casino, now that person's land casino is closed, the reason for the lack of visitors, in short: he switched to an online casino, I asked exactly what you asked here.
Answer:
That person has never gambled anywhere, whether it's his own gambling platform or someone else's gambling platform, the reason is he doesn't have time, because he has to control and monitor their gambling platform and spend almost 24 hours a day, that reason apart from the risks that I said above, the reason their money has a monthly and yearly turnover, so they/owners never gamble anywhere.