Will my friend be allowed to re-enter Thailand after multiple visa-exempt entries?

A user is inquiring if their friend from Belgium, who has backpacked in Thailand multiple times (on visa exempt entries), will face issues re-entering Thailand for a third time. Most responses suggest there shouldn't be any issues since he has a booked return flight, but some caution about the border crossing situation and advise avoiding specific land borders like Poipet due to potential immigration issues. Users suggest that while normally returning travelers have no problems, there have been reports of individuals being denied entry at certain crossings.