I'd say its good to be up-front with users and actually talk about location.
Most "mapping" apps are owned by the device maker eg Apple Maps, Google Maps and you give them access in the device TOS. So in those cases they don't ask for permissions.
However, newly installed 3rd party apps on current versions of iOS (13) & Android (10) are required to ask for location access as part of the store guidelines. This is to give users some semblance of control around their personal data. If you don't see that request, it's likely that you provided blanket permission at an earlier install date.
So baically you have to ask
How and when you ask are up to you
You don't have to ask for permission when the app is installed. You can wait until location access actually makes sense. In your case that would be after a person decides they want food. You also get the option to put instructions/context on the screen for the user.
Take these two examples:
Facebook would like to access your device's location: Yes | No
"Umm why does Facebook need my location???? No Way..." (last I checked Facebook actually does it that way)
Tacos sound great, but to show you tacos close by we'll need to know your location. We're not tracking your location and don't share it with anyone else. But if you're not comfortable with that, you could just give us a zip code to search for tacos. However, it won't be as accurate and you may have to walk further for amazing taste.
FlordiasBestTacos would like to access your devices location: Yes | No
"yeah you know I'm hungry now and want the closest good tacos. Of course I'll give you access!"
Mom always said, "it's not what you say it's how you say it." I think the same goes for how you ask for things. Make a good arguement and let people decide based on merits. Just make sure to provide a decent if not perfect fallback.