I would think that the wedding celebration at Cana would qualify as “fun”. There was certainly a lot of wine involved, and the celebration must have gone on for a while, perhaps days, to go through that much of it. I doubt so many people would have stuck around that long and drank that much wine if they weren’t having fun.
Beyond that, one must consider the times, place and culture. Most people, other than the very wealthy, had little time or money for leisure activities, sports or the arts. They worked and struggled to survive. Even then, I expect that they had “fun” when they could, but it was nothing like what we consider today as entertainment. Plus, scriptures and other religious writings by or about the early church fathers were focused on the meaning and growth of the faith, not on secular things. Not much was said about what foods they ate, or how they dressed, or about any of their other every day activities. Yet I think the people back then found some time for relaxation, a little laughter, and good times with their family and friends, etc. Just like everyone else has throughout history; even the saints.