Wes: "Hi, I've traveled through time and space to attend this wedding, but wouldn't you know it, I totally forgot I wasn't supposed to be naked for this one."
Picard/Farnsworth: "No problem. It just so happens that we have a single spare uniform aboard this massive starship of hundreds of officers; but it has lieutenant's pips, which might confuse the audience--of the wedding, that is--into thinking you're somehow back in Starfleet."
Wes: "Why don't I just take them off?"
Picard/Farnsworth: "No, dammit! I don't want to have to clip those back on after!"
Wes: "For that matter, why would I even wear somebody else's uniform? I'll just replicate something that actually fits me..."
Picard/Farnsworth: "Repli-wha? What do you think this is, the future? Just put on the uniform and stop exposing the tenuousness of this scenario!"