That annoyed me. In fact most of Half Life 2 annoys me. The whole story seems to be based on creating artificial shortcomings in order to prolong the thing. "Oh no, the teleporter is broken, you're going to have to walk over to the lab." "Oh no, the doctor you've just rescued has been kidnapped, time to go on another dull quest to find him." Now I'm stuck outside some Greco-Roman building, with a shitty rocket launcher, and a distinct lack of ammo, trying to take out near invincible tripods.