In this article (in Dutch) it is claimed that an ancient Roman drinking mug found during an archaeological dig in the town of Mortsel in Belgium, contains the only known instance of the Latin inscription avoca te, translated as enjoy yourself. Similar mugs have apparently been found in Germany, some of which had inscriptions using the verb avocare, such as avoco te, but the imperative phrase avoca te is claimed to be "unique in the history of Latin".
I find the claim that this phrase has never before been found in any Latin text to be somewhat suspect, and probably misinterpreted or exaggerated by the journalist who wrote the article (even though she claims to be paraphrasing a professor of ancient history).
Is there a linguistic reason why this phrase would not have been in general use? Was the now more famous phrase carpe diem already ubiquitous in ancient times, to the extent where no one would think of expressing the sentiment any other way?