I agree, we get more support issues from shared hosting accounts than from the reseller accounts.
Normally because end users often ask questions to learn general hosting, whilst resellers field these questions and only report true system issues.
If I charged for every word-press blog I fixed, I'd be able to retire.
As to the OP question what to do about TOS violations
With CloudLinux installed, most violations are controlled automatically, leaving mainly content violations.
TOS violations should result in suspension of the user account at fault.
However should the same reseller keep having issues over and over you have to put them on a warning.
Once you issue a warning, you will have to follow through if the rules continue to be broken.
Your TOS should be written to protect your system, so if your users break your TOS they are harming your system and you don't want them to host with you.