I live in a very bike friendly country, so culturally closer to Europe in terms of transport, but if you walked into a drive through you may well be stopped by police.
Drive throughs have long since stopped serving pedestrians.
Generally anyone trying this is inebriated.
And since horse riders are legally equivalent to vehicles it's pretty much a "fine as long as you don't shit in the driveway" situation.
That's a social class and location based. The average overpaid techie on HN who lives in the kind of place where all the houses are a million bucks and everyone buys their trophy wife a 4Runner because that's what you need for one kid then yeah, the drive through won't serve you as a walk up.
The Popeyes in Camden NJ don't care if you ride an elephant through the drive through.
You quoted me but I was commenting on my country, an egalitarian country in the Pacific.