My wife just asked me this actually. Here’s what I told her. 

It’s because there’s no financial incentive for them to. If you’re going to commit a federal felony and go away for 10+ years do you want it to be for an altruistic act that probably has little benefit to yourself? Or for ransoming $2.5 million from a hospital? Probably the latter.

There’s also no central location for all those records. There are many different loan companies and they all have different systems, different backup schemes. It’s not a trivial “DELETE * WHERE 1=1” kind of database query.