Mortgage vs. Free and Clear Tax Sales

[Aaron Millis]

Would it be fair to assume that most properties that go to tax sale are owned free and clear vs having a mortgage? Because I don't see how/why a mortgage lender would allow a property that is delinquent to go to auction when they could just pay the taxes themselves and foreclose on the owner to protect their investment. I guess this is assuming there is an escrow account though, which I also assume most people have rather than paying everything separately. I don't know what a scenario is where the bank is better off letting a property go to auction..