First of all, ONE shot indoors can cause PERMANENT DAMAGE.
Second, although you may not HEAR the shot, the auditory exclusion is happening in the BRAIN. Your ears will still take a beating.
Ok, I have a set of electronic muffs within reach of my nightstand gun.
Will I use them if someone kicks in the door? Not a chance.
Will I use them if I hear something suspicious and go to check it out? Well, so far I've forgotten to so the answer is "Probably not."
But I MIGHT remember one night and that MIGHT be the night that I have to crank one off. So they're handy--but that doesn't mean I HAVE to use them.
If you reach for muffs when things are definitely in a SHTF situation you will probably die with them in your hands.
BTW, if you get a good pair of electronic muffs they will NOT distort the sound and they will have binaural amplification which will not affect your ability to direction find using the sound. They can amplify considerably which is an advantage in some situations, but you can set the amplification level to whatever you want. Normal, for example.