I live in the US in a "platinum rated" bike city (so there are a relatively high amount of bike commuters) and have gone through drive throughs on my bike a handful of times. Every time I have been served but told not to do it again.
Pedestrians are not served at drive-through windows at least in part because they are more dangerous to the workers. A driver at a drive-through window can't open their door, the window is very close to the drive-through kiosk but the kiosk is usually much higher (in a sedan) making it hard to climb out through the car window...they've also got a license plate.
During the pandemic most fast food places locked their lobbies and only did drive-through, which meant truckers couldn't get food because workers wouldn't serve them due to policies the companies refused to adjust.
I remember some police departments were volunteering to go through the drive-throughs for truckers.
The nightmare is being shot through a drive-through window and not even being able get a license plate. I've never had a car driver's license (only motorcycle) and I completely get it.
They're not staffed the same way at night as they are during the day.
As much as the political salesmen love to emphasize the differences, Soviet style bona fide government central planning and American style corporate central planning have many commonalities.
I've had some luck asking a stranger in a car to trip the sensor and then back up so I can order and walk though. Once your order is in its more work to say "no" than it is to say "yes but don't do it again"
Some cities like Portland, Oregon have made it a violation of city code to refuse to serve pedestrians and bicyclists through the Drive Through window if the lobby is closed.
There are still some businesses that violate this, but at least you can report it and they will be fined, and threatened with revocation of their business license.
Good. Let's make this federal law. These restrictions are ridiculous and we stand no chance of eliminating car culture without eliminating them. I wish I was kidding, and I wish it were just a trollish joke to say "you should be able to bike through Taco Bell at 2am", but if we're gonna eliminate car culture in the US, we can't just do it in the downtown cores of Chicago, NYC, Seattle, SF, etc. We gotta do it everywhere, and a lot of "everywhere" in the US is drive-thru this and drive-thru that, especially once you get out into the boonies (which of course need more infrastructure work to become bike friendly in their current states, but also, rural bike trails can and should exist, but there'll be little reason to use them if you can't stop anywhere along the way to take a break - and the rabbit hole continues from here)
After 9 or 10 PM that's exactly how it is here in TN, USA. Dine in is closed and the drive through won't take you on foot or on a bike. I think most franchises have a blanket policy against serving people without a car to intentionally exclude... Certain People.
But why? They would have to allow these same “Certain People” in their lobby from 7am until 9pm when their most affluent patrons are probably coming in for lunch, after soccer practice, etc. At the drive through there is barely any interaction between staff and customer much less between customers.
I would assume the homeless, certain income ranges, etc. That's the real reason to close the lobby but keep the drive through right, so people aren't hanging around in it and resting at night?