i had to stand in front of a cashier to read the menu at mcdonalds b/c i didn't have my glasses. when you walk up to them they think you're gonna order. so i had to explain.
i believe a lot of ppl find things like that so socially awkward they would prefer to just not read the menu and order something from memory, or even look at online menu on phone. and a lot of people don't talk about this kind of thing, either, because they find it embarrassing or shameful, so you may underestimate how common it is.
i usually don't wear my glasses b/c i can see fine to get around and do stuff. reading menus i can't hold in my hand (the kind behind the counter) is actually the only problem i run into much when walking around without glasses, and i don't want to wear glasses in general just for that one thing.
i might have looked online on my iphone if it was reliable b/c even standing at the closest point in the store to the menu it was still somewhat difficult to read. and the menu is computer displays that keep changing instead of static text. it's also very badly organized. i find it strange that mcdonalds uses technology to make their menu way worse than a regular menu. they could have some regular menus available you could hold, or just post one on the wall somewhere, but they don't. if it's because they want to change their menu often and feel they need computer screens instead of just printing out updates, they could put a computer screen on the wall with menu text that doesn't changing during the day so people could actually browse their entire menu (it could even be a touchscreen where you can flip through the pages if they want to be fancy and their menu is very long). however, i don't think you can reliably look up the exact menu of a particular mcdonalds location online so i didn't try that even though the store menus suck.
the reason i wanted to read the menu is i ordered jalapeno doubles from postmates (delivery people service) from mcdonalds a couple days ago. and they said mcdonalds doesn't carry them anymore. so i was trying to check the menu for them. i didn't see them on the menu but the menu is so confusing i didn't think i'd actually viewed a complete list. so i asked the cashier. they do have them. yay! but what the fuck is with the incompetence of the postmates person who said they were at mcdonalds and they no longer carry jalapeno doubles? they just do. :/
in addition to jalapeno doubles, which are great and i recommend them, i also ordered the daily double which i hadn't had before and didn't see on the menu, but had seen online. it was pretty good. i only knew about the daily double item because i saw it on the mcdonalds menu on the postmates website when ordering there, which shows menus are useful! i like to read menus sometimes to browse. similarly i occasionally like to visit grocery stores to browse. (when not browsing, it's mostly better to order stuff online and have it delivered, which saves time and effort. safeway will deliver large orders for cheap or free. and walmart will deliver non-perishables for free if you order $50 and they also have generally have better prices than stores around here. amazon also sells some foods with free delivery.)
anyway my main point was about the social awkwardness of going and standing by a cashier and explaining about not having glasses. i think a lot of people wouldn't do that, or would really dislike doing it. i think a lot of people put substantial effort into avoiding that kind of thing and don't realize they have a problem. but it's really no big deal. you should learn to do it. it's not hard. i grew up very shy, and i can do it just fine. just try it, no one is going to hurt you for wanting to read their menu and making a short, reasonable statement about where you're standing in the zone of the store for customers.