Non-player characters, commonly known as NPCS, can of course flout the normal rules for player character generation and advancement, since they don't need to be balanced as members of the adventuring party. In fact most of the population of the adventuring world will be significantly less powerful and influential than the PCs, since games usually assume the PCs are heroes of some sort. And there will be a few NPCs who are substantially more powerful than the PCs as well - the rulers of the land, corporate barons, senior wizards or superheroes, or what have you.

Of course if any of these ever has reason to turn into a player-controlled character for any reason, the odds are highly in favour of it being one of the less powerful types. Both for reasons of statistics, and any GM would be nuts to allow a player to control one of the latter types of NPC.

Transcript

R2-D2: I don't trust you. You're short, furry, and primitive. What are you maxing?
[SFX]: < boo-boodoot ziku-bafiku beziku-bipizung blip-plip-ding bippity-ping >
Wicket: Other than Charisma and mercantile ability?
Luke: They're NPCs; they don't need to be balanced.
Han: Hmmm. I want to play an NPC next time.
{beat}
R2-D2: Well, good work getting us out of that mess, Threepio. I miss being a flying droid.
[SFX]: < bippity tong po-fipgi-doip-bedoop oobloo ping-ta bedoop >
GM: You know, if we'd just taken flying in Robot Utopia we could have escaped that island easily.
Luke: Yeah, you never told us we'd be stuck in some robot zoo for the entertainment of humans.
C-3PO: It wouldn't have been a challenge then, would it?
R2-D2: Well if we ever revisit that campaign, I'm taking flying for sure.
Leia: In what way was this a "Utopia"?
R2-D2: Some of the humans fought back. For a while. That was fun.