It's like when you are trying to buy Project Zomboid but it is too expensive on steam so then you go to G2A and get the key for the game for like half the price, for people that feel bad about piracy but doesn't want to pay full price, G2A is the way to go.
Guy 1: Hey man let's play Project Zomboid!
Guy 2: Nah bro, it's kinda expensive
Guy 1: Get the key on G2A then, you broke ass
A key reselling platform that is known to sell stolen game keys generated through CC fraud. Contrary to popular belief buying from G2A is financially damaging to the devs and you incentivize CC fraud.
Some poor bloke: I want to play Factorio but i am broke af, lemme buy it on G2A i don't want to pirate it.
Another bloke: Mate don't give money to some dodgy seller. Just pirate the game.