Sure, loops for rehearsal convenience and for recordings. Right now I'm working on a track where I've got so far:
one kick being synthesized by a VST
two samples of synthesized snares layered together
four layered shakers - two acoustic samples and two synthesized samples
one other synth shaker sample in a separate layer
one sample of me smacking my double bass body with my knuckles
four miscellaneous drum patterns with an acoustic sample of an African drum layered with a vaguely similar synth drum sample
two different reversed cymbal samples
one synth hi-hat sample
So that adds up to 20 layers.
Pretty different from programming "drummer playing a drum kit" style drums - I do some of that sometimes too. Usually MT Power Drum Kit which was rereleased as a freebie last year - it's not the biggest but the most convenient, there's a lot of compression and EQ baked into the samples so it's got a "post-2000 rock drums" sound without much trouble. I have some much bigger kits, DrumMic'a which is over 4 GB and a Yamaha kit which is something like 1.7 GB, but don't use those nearly as much. For a lighter, more retro sound I have various small free kits. I don't like too much realism anyway.
It's that constant and obsessive, "never-ending" process of finding new sounds.
What's interesting - the more you have the more you need.