IMO, some collaboration that could be considered acceptable in other courses would be deemed academic dishonesty in CS50, thus it could be that some of these cases were inadvertent due to a failure to play close attention to the rules.
I do know that some students who take CS50 find themselves far outside their comfort zone - it could also be that some students resorted to “not reasonable” actions because they thought that was the only way they could pass.
That’s all conjecture though!