That isn't true at all: Often competitive players are required to use the tournament organizer's hardware anyways. And often competitive players form groups to

That isn't true at all: Often competitive players are required to use the tournament organizer's hardware anyways. And often competitive players form groups to play in, so everybody knows each other even while practicing. You'd probably want to be on a LAN to minimize the risk of this happening accidentally. So in practice, I don't think it would matter too much even if money was on the line. You would just have to take appropriate precautions, and watch to disqualify people for cheating.