Where on Voyager besides the replicator would clean a uniform?
They don't even have closets or dressers to put away clothes in.
I find it ludicrous that even in the 24th century, they don't have some kind of washing machine. After all, given how B'Elanna can flange up just about anything, why couldn't she make a sonic shower/cleaning thingy that works on fabric? Assuming, of course, that the Federation doesn't already use such technology.
And they do so have closets; there are numerous references in the fiction to so-and-so taking their dress uniform or civilian clothing out of their closet. I forget which character on which series (Julian, on DS9?) forgot to pack his dress uniform.
After all, given the way energy was being rationed at times, the crew would need a way to clean their clothing without having to replicate new stuff all the time. Otherwise, they'd be running around naked when they didn't have enough energy to spare.