I heard a rumor once, and I have no idea how true it may be. But the rumor goes something like this: parking lots, beyond being ridiculously lucrative and turn-key businesses, are also fantastic money-laundering or tax-dodging opportunities. And so many of them are owned by shady characters, or shady companies. These types don't necessarily want to deal with things like processing credit cards, or getting into paper…
This is from an online class I took called "Texas Essentials of Real Estate Investment".
"With the elimination in 1986 of preferred treatment of capital gains profits and accelerated depreciation allowances, real estate investments lost much of their glamour as tax shelters. However, the tax laws have preserved other sheltering aspects, including tax-free refinancing, pyramiding through refinancing, special exemptions for profits made from the sale of principal residences, installment-sale deferments, exchanges, and inheritance tax exemptions."