The people I had observed having issues basically played to the point of failing school classes due to chronic sleep deprivation, had atrocious performance in work post gaming session (he talked about playi by game till morning openly) or basically checked out of family life entirely making partner basically single. Let's say that formely gaming friendly wife build up huge aversion toward games.
I knew multiple of these and none of them played farmvile nor anything like that.
I believe people like your friend exist, the farmville top cant be composed of people having healthy relationships and jobs. But they are not around me. Around me the worst were among pc/console players, usually people who self identified as gamers and took it as point of pride.
If we are talking about spending, thankfully the above person did at least restrict themselves to <$100 per months on boosters (or at least that what they told me), but you should be aware that in-store revenue outnumber sales revenue in basically ever game regardless if its on phone or pc (not sure about console but my guess is that the same is true). There is a reason why almost every game company has shifted focus away from game sales and into in-game item sales.
> Rage and affected mood are two different things.
No. Mood swings because of a game is the same regardless if its short bursts or long and moody. If a person allow a game (and the social groups in it) to have lasting negative effect on their mood then that is a problem regardless what kind of game it is.