Foam earplugs are generally more effective than muffs. The best muffs are about 24-25 db reduction. Most foam earplugs are 31-33 db reduction. That extra 6 to 9 db reduction is considerable.
Buy ear plugs (or muffs), shooting glasses, some spares of each for guests (I keep a wad of foam plugs and three sets of muffs in my bag, and half a doz sets of glasses) in your shooting bag, along with stapler, spare staples, markers, etc.
DO use this equipment. Don't let anyone tell you, "oh, you'll get used to it." No, you'll get deaf, not used to it.