I think those are LAIZ!  Stuff dont replenish in safehouses
anyway, I usually use safehouses to put some unique stuff that I never use in the footlockers. Maybe I'm going to make a museum out of one someday and make a video of it. I just tried displaying some guns in the NoVac motel and it's actually not even that difficult (laying them down and stuff)
heres a example of one of my safehouses 
NCR safehouse:
3x hunting shotguns 
5x snipers rifles 
18x C-4 bricks + 2 detonaters 
3x anti material rifles
10x assault carbines 
2x missile launchers
8x grenade launchers
2x trail carbines 
and a ammo table
i use safehoueses as caches for emergencies (might make a topic about good cache locations)