You also pull a bush out of thin air and shuffle around with it when you want to sneak.
I can't take arguments about silly things breaking immersion seriously, with this game. The whole game is composed of silly things.

If your argument is that the minigame is poorly designed, I am betting you don't fully understand how it works - and I don't blame you. It's not well explained.

Every time you win, at RPS, you get some points. First person to get 10 points wins the argument.

The number of points you get is based on your Charisma. More Charisma = more points per win.
The number is further modified by what option you chose (charm, intimidate, reason). One of these is the right choice, and increases your number. One is wrong, and decreases. One is neutral. This choice is different depending on who you're talking to, and the context of your conversation. If your perception is high enough, the game will tell you which option is right/wrong/neutral.

It's essentially comparing your persuasiveness vs their persuasiveness, and adding in a bit of randomness. Kind of like how attacking someone works.

If you want to win arguments, increase your Charisma. That's what it's for.