For a large corporation with a substantial legal team, that might make sense for many situations...they've already paid a baseline cost for the capability of near-continuous engagement with litigation of some kind. For many small/medium businesses, it can be a large additional cost. Then it becomes a question of "am I so willing to screw this person I owe money to, that I am willing to screw myself in the process?"
Showing up in person is a way of indicating you're willing to make it complicated and/or expensive to make you go away.