Here, the quick response is "yes" Almost all, websites that offer 100% deposit bonuses have a cap on how much can be won. This cap will typically be $500, however it may differ from website to website and bonus to bonus.
If a site didn't set a limit and the high stakes players made large deposits that the site would then have to match in incentives over time, that site could be placing itself in a tight place.
If a site didn't set a limit and the high stakes players made large deposits that the site would then have to match in incentives over time, that site could be placing itself in a tight place.