I play mostly dive bars featuring original music where you get 10 minutes changeover time between bands if you are lucky. Only the first band gets a soundcheck. I've never seen a musician using a computer on stage under these circumstances. I've also played in cover bands where we did three sets and had the whole night. I imagine that I could have done computers, wireless, IEM, floor monitors, and other fancy setups, but I'm really comfortable with the old-school rock and roll guerilla approach.
I guess the point I'm making is that there are lots of different musical worlds out there, from dive-bars with one outlet on stage and vocal-only PA's to permanent big-dollar worship installations that are "studios-on-a-stage".