TF2 can be a cheap game.

Snipers headshot you from inside the spawn, perma-invisible spies just waiting for you to start shooting to stab you, invincible medics, auto-aiming sentries, soldiers who can one-shot half of the classes with a single rocket, the list goes on.

But having a demo cross the whole map to camp the enemy spawn, killing people again and again (some even aware there's a trap outside) - THAT is unfair.