Eg. pokemon (gb/gbc/gba) with cheats is still a great game.. you can explore everything, infinite hp/pp, catch-all pokeballs, go everywhere, see everything, catch everything you need/want, fast power-ups and evolutions, without the constant grind of powering up your pokemon and running back to pokemon centers.
Same with games like GTA (although, there is not a lot of grinding here)... you can still play through the whole story, do all the missions even when invincible, have a lot of fun, but without the "getting kiled" parts and restarting the same mission sequence 50 times.
Somehow in modern times, cheating (to avoid the grind) has turned from inputing some random combination of commands to paying actual money for premium crystals or whatever, that give you a competitive edge against AI (and real-life) enemies, or in some game (clash of clans, etc.) to just make the obsurdly long wait times shorter. I get the monetization aspect, and developers getting paid aspect, but eg. Age of empires developers got paid too, and i can still type "coinage" in the chat window to get 1000 gold without paying extra money.