What they should or shouldn't do is irrelevant, but obviously they are a for profit operation. There is a reason they set up in Walmarts.
There's an interesting argument about the whole tax prep process. Basically, it could be streamlined to a large degree. The majority of folks are engaging in a theater of checking the math, without really having a great grasp of the math. Like, the government has all our docs and could just run the stuff themselves, mail us some forms, say "check this, re-do if there's a reason to," and go from there.
The modestly-logical argument against that is that people will not really check, and extra charges will get slipped by us. I guess this makes sense, though I kind of doubt people have a 360 degree grasp of all their tax stuff.
The more cynical argument is that the tax prep lobby is powerful and well funded. QuickBooks Online, TurboTax Online and Credit Karma are one company and earned $6.6 billion. That's a lot of lost revenue for someone.
And the most cynical take, which I don't have much time for but find intersting to think about, is that people feeling poorly about taxes is a great base for political messaging, and some folks in those roles would prefer that agreement level remain high.