I've bought gold on WoW many years ago. Everyone done it as far as I was concerned and it made life a bit easier.
I've bought ISK on EVE once simply because I was tired of grinding low-level missions to earn money, but not enough to do what I wanted. Used it to buy and kit out a Battleship (as I had been training for a couple of months prior to properly outfit it) and run high level missions. To be fair to the game developers, they cottoned on and removed the amount of ISK I had bought from my wallet after a few days, but in that time I'd managed to amass that much ISK and more through the higher-level missions it didn't really matter...
I took advantage of naive RuneScape players in the early days by buying rune essence at under market price and just flogging on at a mark up. Made so much gold it should have been criminal. It got to the point where I had regular people I used, that I would message them over MSN Messenger bossing them to get on and mine for me!
I get so easily wound-up by one of my mates on Rocket League. He's not a bad player in terms of ability, but he does nothing but ball-chase and gets angry that "he's the only one doing work". He doesn't seem to understand how rotates work.
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I'll ask him to stop ball-chasing and end up just doing it myself...
I'm getting tempted by SWBF2, more-so now that microtransations have been "removed". I loved the originals (yes I know these pale in comparison) and never played the first Battlefront despite thinking it looked pretty decent.
I can't help but shoot towards teammates on PUBG with a silenced pistol and play along as they think they're getting shot at from miles away. It's even better when someone is spectating and having to play along.
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I got to the point in CS:GO that I was so bored of the game's mechanics and netcode that I would actually watch films and TV on my second monitor in the middle of league matches. The game was / is just so poor in comparison to the previous games!