It might not be the the default behavior to display the tickets in the catalog, but the category shows up by default. Seems kind of silly to display the category if it’s empty. I see others here expressing the desire to display tickets in the store, along with up sells and cross sells, etc. so perhaps you should give people the option to do so in the settings, and have the tickets automatically remove themselves when the event is over.
I’d make a post in the feature requests section, but I’m all out of credits there as there are numerous features missing from this plugin that I have mentioned or voted on.