I remember when I first entered the adult world paying my bills online was super easy.
These days, I feel like half the time I log onto some doctors office or mechanics website to pay a bill the site is like "yeahhhh, idk why but I'm just not going to accept your credit card. Also the button to the 'finalize payment' screen is grayed out even though you filled out everything."
And they you email tech support and they're like "idk delete your cookies I guess? That didn't work? Guess you gotta mail us a money order."
They don't take credit cards because it costs them 2.5-2.9%. That's actually reasonable to me because credit cards are basically a tax on the poor. When the same price is charged for credit as debit/checks, people with credit get 2% or more back as rewards points and people on debit get nothing.
The one that kills me is when government payment sites are run by a private company that gets to squeeze a fee indefinitely for setting up a really basic website.
Booz Allen Hamilton(the defense contractor) runs the reservation system for federal parks. It's a pretty basic website and in exchange they get to keep 100% of the charge for reserving a campsite, cabin, or park pass.