Very true but the issue also is how often. Sure I think we all play games for long peroids of time at certain times (like a new game release we have been waiting years for) but generally we don't game for that long on a daily basis...Well I have got it up to 4 games at once, though tetris is more to keep my hands busy and the other three involved a lot of waiting.
31 hours of monster hunter 3 is too much, granted I think 31 minutes of monster hunter 3 is too much once you know what the game is about.
As or the matter at hand... I guess I am going with the usual "does it cause you to neglect you, those that depend upon you or something similar? If so then that is probably too much". If it is sedentary gaming then you might need to account for that and there might be some other medical things somewhere (I am never sure which are actual and which are "well if we say this and they at least do something approaching it") but I will have to read up further there.
Ok, so it wasn't a FULL 31 hours, there were some internet breaks to reference some things about the game here and there and check my messages, but it's still a pretty damn long time! Not sure when I started last night, just remember playin past midnight, then it got daylight out, fed the cat, made some hot pockets, played some more, then next thing I know it's getting dark and it's like "There's no wa...holy shit, it's already 6 at night... Wat da fuuuuck?"