Many of us feel power amps sound best when plugged directly into the wall outlets. But these amps tend to have good internal protection.
I’ve never seen such an amplifier. At best I’ve seen an MOV or two in there.
Obviously whole house surge protection would help shield other costly appliances, but how valuable for good power amps?
I think that consumers have very different risk profiles depending on your experience and your equipment. There are people in North America who have never lost equipment from an electrical surge. None of them live in the Southeast. So, speaking personally I can’t imagine spending big dollars on electronics and not having something, anything, to reduce the chance of surge damage.
Also, from my own experience, I know by observation that my amps get fed better power more consistently by using a Furman with voltage regulation + SMP/LiFT. Whether I was living in an apartment with 130VAC or here in a detached home with 10-15V seasonal variations and power fluctuations due to the AC coming on or off, brown outs and monthly power issues I know for a fact that every day, every hour, my integrated gets fed well regulated and clean power.
It also sounded a lot better when living in a densely populated area to have Furman than not.