That’s for accessing the website, not for sending your traffic via TOR to Mullvad. I don’t think they have a built-in way to send traffic to them via TOR without going through an exit node.
Oh, huh that's odd, why provide website access but then not actually product access when your product is a network service. Didn't think to read further than the headline because of that I guess, thanks for correcting me
same as with cash and crypto payment method it's to minimize data exposure outside of the service itself. If you don't trust them to connect with your ip why bother using a VPN instead of just tor.