I'm not sure I totally agree here, but it's complicated and because I'm not working won't elaborate. Sure, the tenants have to go bust prior to the landlord, but not all commercial landlords are wealthy people...Many are self-funded retirees who rely on the income from commercial property...And there's always costs to holding property that needs servicing. So anyway, this answer is a complex one and when I'm getting paid to answer it I'll address it. It's not as simple as you suggest though.