I carry a pair on me at all times, too. And it’s a bigger help than one might realize.
If someone is sensitive to loud noises or particular sounds, earplugs can help prevent them from being overstimulated by those sounds. If I enter a loud bar, I put them in. If I have to be around loud or crying kids, I put them in. Loud college party or hockey game? Ear plugs. Crowded fair? Ear plugs.
They allow me to stay in social situations that I would otherwise have to leave. It makes much more sense for me to put my plugs in than to expect kids to be quiet all the time. Or for everyone at a party to be respectful just for me.