Yeah honestly, I bought Tarkov second-hand for $8 and even then I felt like I was getting ripped off.
It's probably not news to anyone but the game has extremely lax anti-cheat controls.
As for why people would cheat in an online game, it always seems obvious from a psychological standpoint, but the cheats for Tarkov are so egregious they're like full blown developer offline DEBUG TOOLS.
I don't mean "oh no, aim assistance, and they can see you through walls" -- the cheat tools are hooking into features of the GAME ENGINE ITSELF, allowing players to see:
PlayerName, Current HP, Current Level, Full inventory contents, currently equipped weapon, position, heading, estimated value of inventory, estimated value of your account, age of account creation, and so on.
They can also: Teleport, FLY, increase or decrease their run speed, jump height, and so on.
The cheaters are basically running around with admin privileges in the game, and the developers don't give a flying fuck. It's like GTA5 levels of cheating.
Why would anyone play such a game, much less pay $150 to be abused by people? You can slam your dick in a car door for a lot less.