I think your sitting vs. standing preference has more to do with your personal experience playing games. Those of us who grew up in the 80s and hung out at arcades are used to playing arcade-style games standing up. Sure, we also played console games such as Atari and Nintendo, but arcade games were a different experience. Many younger gamers never had the real arcade experience and their gaming was mostly on the couch, or beanbag, or just sitting on the family room floor and playing. So preference sitting vs. standing probably has more to do with your personal experience.
As others have pointed out, arcade games, at least the classics, were generally shorter in length and more appropriate to stand and play.