There's no justification from a pure convenience standpoint, but I could respect the pettiness if the electric company ran their shit like one local government office in my hometown, where there was this small annual fee they charged like $9 for...but then to pay it, you could either mail in a check, hand deliver cash or check or card...or pay online...where they added a $5 "convenience fee" to a sub-$10 payment.

You bet your ass that I paid that shit in person every year, in loose change, and requested a receipt (which they had to write up manually because they didn't have a system to process and print one).

Most corporate bill portals I've personally used were terrible and charged me a significant convenience fee for using them.

Well, the funny thing is... it IS somebody's job, and they get paid for it. There more they push "self service" the less workers they're hiring and paying wages to, and the more your ever-increasing grocery bill just goes to pad some executive's bonus so they can buy a bigger boat or whatever.