The food aspect used to be handled by large numbers of diners that had good quality food (relatively obviously) but has been replaced in large part by chain restaurants.

This might be a bit rosy of a view of diners -- I'm sure plenty were mediocre or bad. Not exactly the same, but my dad told me about traveling before and after cheap chain hotels sprung up everywhere, and said a real benefit of chains was that even if the quality wasn't spectacular, you knew more or less what you were getting, which is itself valuable.