Greetings, all!
To begin, at its most basic level, resetting hunt marks can be considered a grief tactics violation. This post will be discussing grief tactics in general as a violation of the rules, and that general discussion would apply to this particular topic, as well as any number of related topics (MPK, zone disruption, etc.). If you would like a point of reference for this rule, you can find it under the
FINAL FANTASY XIV User Agreement, specifically section 3.2:
Disruption. You may not in any way disrupt or interfere with the Game experience of other players, including the disruption of Square Enix's computers and servers.
LGM Enkrateia