Of course, and Etsy has tried many rules that have punishment attached. Like most communities or marketplaces the punishment is removal of your listings or suspension of some account privileges.

Unfortunately my experience is they were very inconsistent with application of their rules, and often closed stores that didn't deserve it, sometimes repeatedly, while obvious rule breakers operated for months. Sometimes they remove items, sometimes esp. in the past you just come to log in and your password doesn't work and your store is gone.

While they also had issue forming reasonable procedures and rules, much of the problems are with application of their rules, as in having enough employees and managing training them effectively.