If the cameras are at home and I don't plan to take pictures then none of them are loaded. If I carry a number of cameras for an outing or trip then all of them are loaded.
Right now - thankfully - only 1!!! I like to get a roll shot so i can process it. That said, that 1 roll is in my Mamiya RB67 and i desperately *need* to dig up some inspiration to finish off the 3 or 4 exposures on it....
Five, all loaded.
Canon EOS 300 with HP5
"" "" FP4
'' '' PanF
Spotmatic II HP5
Rollei B35 HP5
I can't remember the last time a film was in a body for more than 2 weeks before it was finished, so it should be ok.
See, that's what I try to do, but for the most part convince myself not to cut rolls short... For an amateur like me, film is too expensive to not shoot the entire roll, or most of it anyway.
An Olympus rc with panatomic x, a canon vt with fp4+, and a canon Demi s that seems to always be loaded with trix or tmax400 (this one takes forever to shoot with 72exp a roll). Only my cameras I don't use often have film loaded in them. I like to finish the rolls at the end of the day/night when possible.
A Kowa SixMM with some Portra 400 and a Pentax KX with Fuji Pro 160S. I've had a roll of re-spooled Acros in the fridge for a while now, I'm thinking of taking it out soon and loading up the Kodak Reflex II.
I've got 2 of 3 35mm bodies with film loaded. I'm sure it's not the best environment for film but I've processed a roll out of an old ricoh with gaffer tape holding it together after 5 years and it looked fine. So, I don't sweat it too much
I stopped loading cameras with film unless I'm taking one for an outing because of the following:
1- I forget what type of film is loaded in which camera.
2- I like to keep the time between film-in-the-fridge and film-in-spiral-tank to a minimum. usually less than 12 hours.
3- when I'm bored I like to play with the cameras, cleaning them inside and out, dry firing the shutter and just general fondling. That, of course, would be difficult with a loaded camera.