I didn't either, until I packed a bag for the World Science Fiction Convention in Chcago in 2000. I couldn't figure out why my suitcase and clothes all smelled so strongly. I didn't know what it was. I had gotten so used to it that I just didn't take note of it until was well away from that environment. I had almost 350 meeces at that time, after rescuing a half a petstores worth of rodents that were otherwise going to be put down. I don't care if you clean our tanks every day, it will smell like meeces.
Now I appreciate the difference between a clean mousery and one that has something amiss like wet bedding from the water bottle wicking in to the litter, or other things like a dead mousie on a warm summer's day. The first book on keeping mice that I bought recommended wearing a nylon jumpsuit while doing mousework, and I didn't get it. I got it now. I tie my hair up in a bandana, and usually just do the mousework in shorts and a T-shirt which is changed almost ever night for fresh.
One of the little things I want to do in my mousery is install the kind of vent one would have in bathroom. I think that would be really, really nice, both for the sake of economy in heating and cooling, and for reducing ammonia and other odors. Right now I have a large air cleaner with charcoal filters and several large bags of zeolite that are swapped out to recharge in the sun every week or so.