The grooming room always has 3 to 6 hair dryers running. It is very noisy and can over years effect your hearing. Foam ear plugs are cheap 5 pair under $3. He chooses not to spend $12 a month to protect his hearing.
I used to wear the disposable style earplugs when using my gas powered equipment, but they make my ears itch. Now I use over the ears muffs, more comfortable for me, and I think they do a better job of blocking sound.
Of course you do sacrifice your good looks with muffs...