nice to see you suggest the transit passes for tenants. I've been saying that for over a decade. Even tried to suggest same for employees at a tiny strip mall to discourage them from driving--buses on 2 side of the triangle lot both 2 stops to BART. My idea included the addition of a "zipcar" or = for the employees on the day the kid calls from school having barfed... etc.
Beyond the regressive aspect of sales taxes, as you point out, because taxable purchases are easy to stop in tight economic times, they strangle transit precisely when being able to commute more cheaply to what few jobs are on offer is critical. Decades ago, it was claimed that the NYCTA spent as much collecting fares as they took in--not stats I ever saw, merely a political statement seeking fareless subway. Anectdotal complaints by anti transit folks claim SF Muni is de facto free yet I randomly am challenged by fare inspectors. BTW, there is a Hungarian film called Kontrol which features fare inspectors and crews on the Budapest metro--worth seeing. (as a bonus there is an ancient Greek subtext)