> imposing a vacancy tax

That might help a little, but you won't notice. Beating such taxes is done with low value businesses. A mattress store is a typical case, good for holding larger spaces with almost no capital cost: a low overhead business used to hold a retail property until values appreciate. Smaller spaces are held with little clothing stores nobody shops at, or wire transfer shops and such. There is a plethora of such operations holding real estate everywhere, barely breaking even or losing modest amounts of money.

It's compelling to imagine there is some brilliant tax fix for every ill, but investors are a lot more agile than tax authorities; they make their living solving these impediments. Handling food is one the costliest ways to hold a commercial property, so that's rarely how its done.