My 24 hour experience says that no one really wants breaks. A break is just killing time until you get to play, and is an unwanted opportunity to get more tired or fall asleep.
What would be worse than breaks is slaughter pairing for a full twenty four hours. Aside from evening out play times between groups (which is good), it would be awful from a competition point of view.
The less skilled players would be getting killed round after round, while the best players would be cruising through, with very little competition. Actually they’d be engaged in bitter indirect competition with the other top players who are in other groups…hoping to outscore someone they aren’t even playing against.