well, we have two garages here. An attached two car and a detached two car. The attached is the "clean" garage. My dad and his wife park their Subarus in there. There's a workbench, and my dad keeps all his tools in there, but not a lot of actual work takes place (this being because my dad got tired of working on his own cars and just takes them to a mechanic for most everything).
In the detached garage sits two of my dad's old trucks. One is a '78 chevy and one is a '53 chevy. The '78 runs (usually), and the '53 is fairly permanently parked. This is the working garage. I was just down there today changing the oil in my truck, which involves pulling the '78 out and moving my truck in. It was nice because it was chilly, raining, and windy this morning, but I could change my oil in the relative warmth and dryness of the garage. This garage gets used the most for the dirty jobs and such. But all the garages still have cars in them.
It does bug me when my dad doesn't pull the Subarus into the garage because "we're just gonna have to get them back out in the morning", and leaves the garage empty all night. This will change once we get our garage door openers installed. Right now it is kinda a pain to have to get out, open the door, pull in, and then close the door...
Oh, and we do have another 3 or 4 car garage on our property (probably closer to 3, but it just has two sliding doors on it, so it's hard to tell), but we're not allowed to use it for 5 years because the guy we bought the land from has a truck and an old Buick in there that he claims he's gonna restore

. It was all in the agreement that he gets to use it for 5 years, but after that we're gonna have even more room

.
Oh, and we have the barn, too... the lawn tractor sits up there, and we also have 2 horses that occupy the lower level.
Anyway, to answer your question, our garages get used to store and protect vehicles, most of the time. We keep them clean and not loaded up with a lot of junk.