It all comes down to local demographics. In many car centric areas, car drivers make up maybe 85% or higher of the workforce. And of that 15% of the workforce that doesn't get around via a car, they might be making something close to the federal poverty line. In other words, for some of these downtown businesses if you make it unattractive for drivers, you really do dry them out and force them out of business. The guy making $15k a year riding the bus isn't interested in your $15 sandwich for lunch. You are gone and whats going to appear in your wake is probably a place where someone making $15k a year could afford for a couple dollar lunch, probably something like a 7/11 or a mcdonalds.

In other places, people who use transit or bike around on average might be much higher income and could support different sort of businesses.