“N/A” Beer That Has Alc??

Hi guys. I stumbled across N/A beer (Tom Holland’s Bero to be exact) and was honestly confused. I don’t drink myself cause I’m allergic—but realized that the non-alcoholic beer…. has alcohol and you have to be 21+ to buy it at a store?

I am not at all educated on this but genuinely curious and confused as to why there are beers—marketed towards sober people/those recovering—that has alcohol in it? Isn’t that like, against the point? I get you probably can’t have an alcohol like beverage totally without alcohol but doesn’t this defeat the purpose? Maybe I’m a complete idiot but I was confused by this and just wanted some insight 🤷‍♀️

Edit: Yes I understand it’s a small amount and comparable to like Kombucha (I think) but still.