If you are to think deep about the legal rights of all the involved..it turns out this is a very complicated matter.
As long as there are no authorities or regulations to deal with such cases, no other than a real mess would happen..
Let's say I'm an amateur in chess and I go for a weekend tournament just to play chess for fun. I pay the fee and enter the open tournament. Then I have to play against this (or other) man in the first round. What to do? Play...or complain to the organizers? On what ground? Suspicions?.. Do I have to buy an electronic set in order to catch a possible fraud?
Or the other case: I'm a professional in chess and I enter an open big tournament which takes time (let's say a week). I expect to win this tournament or at least to be in the first three.. And then I have the misfortune to meet this guy in the 7th round.. What to do?
As per the tournament organizers: they call their tournament "open".. But if they don't allow him to participate, is it really "open"? Or closed? Or "just for friends"?
What if I (as an amateur) win against two GMs in a row just by accident (or on account of my deep preparation taken from my correspondence chess analyses)? Would they suspect me in cheating? Would they complain to the organizers? Would I be let to play in the next tournament because of such suspicions?
And if I wouldn't, can I take my lawyer's advice and bring this case to court pleading discrimination?
Do I have to continue?..
As you can see, nothing is easy as it seems. And I think all sides lose in this case.