I don't know if it's everywhere, but here in Germany the profit margins on the food tend to pretty low, and the restaurants try to make up for that by selling drinks pretty expensively.
So for takeout, I just order food, and often just drink tap water. I also assume I'm not the only one doing that, so for the restaurants, a significant part of their profit dries up.
They'll have to adjust to that somehow, most likely by increasing food prices, or by cutting into the extra profit from rent differences that you have laid out. If they do exist, I'm not yet convinced.
In the US ordering (free) water is common for casual restaurants. There is a lot of profit to be made from selling alcoholic drinks, but that’s not in everyone’s business plan.
So for takeout, I just order food, and often just drink tap water. I also assume I'm not the only one doing that, so for the restaurants, a significant part of their profit dries up.
They'll have to adjust to that somehow, most likely by increasing food prices, or by cutting into the extra profit from rent differences that you have laid out. If they do exist, I'm not yet convinced.