@masukomi I think a lot of it is just bad habit, yes.
But then I also get the impression that a lot of RPG design is just that. I've spent a lot of time analysing different systems and talking to their makers over the years, and most of them - some more honestly than others - basically shrug and say "I tweaked the house rules based on D&D that I enjoyed most".
Which is IMHO fine in and of itself! It's just that it's possible to do differently, too.