Not always the case, and certainly not a 'no' to cheats being fun sometimes. Some cheats in games are purely for fun. You've never run around as a buring wireframe biped bat in shadowman 64 or flown a chevy through the star wars universe, I guess? =P

If developers accept leaving in their shortcuts and don't have a policy for removing them from release versions - then those that are left in are left in deliberately by someone. If you see those cheats I mentioned earlier as 'unlockable extras'; having to dig around in binary to reinstate closed code paths is just a more convoluted way of unlocking extras. But, that's usually unnecessary because many developers deliberately leave cheats available without having to resort to such means.

In single player; a n00b is happy to find an invincibility cheat or a shortcut, a pro is happy to find an utra-hard mode cheat, I'm happy to find an amusing character skin or a secret room. In multiplayer or 'serious games'; cheats are either non-present or bannable offences. I think; if you find cheating immoral, you miss the whole ethos of 'games as entertainment' by a long shot.