I don’t understand why people think it’s so difficult to build a website. If you let go of the idea that every little site has to look ‘modern’ and have thousands of features, it’s really easy. Stallman’s website would be a good example. It’s super minimalist, and there’s nothing stopping a restaurant from building a site like that too. The homepage can simply list the opening hours and special offers, and then have a subpage listing the regular menu. All you need is HTML and a Server. If you don't want to rent one just buy a Raspberry Pi and host it at the restaurant or at home. Even if you don’t know much about technology, you can always ask a computer science student or a friend’s child to do it for a bit of pocket money.

I think you underestimate how what you just wrote will fly over the head of most non technical people?

Or just host it on squarespace (or something similar).