Gaming's most incongruous weapons

I've never understood why developers insist on putting weapons in their games that clearly don't belong. Maybe they made some sort of cross-promotional deal with a sporting goods store that has an excess inventory of ranged weapons. Maybe everyone thought it was someone else's job to take it out. Who knows. But there's no mistaking these illogical, inappropriate, or sometimes just ridiculous weapons.

Crossbow from Half-Life 2
Let's see. A long range weapon needs to have ammo that travels long distances at high speeds. Yet at a distance hummingbird's wings could alter a crossbow bolt's trajectory and cause it to fly wide of the mark. And in a futuristic world populated by angry enemies backed up by massive firepower, this medieval throwback is downright absurd. What's even more insulting is the fact that your enemies take shots at you with a perfectly good sniper rifle. The combine have a sniper rifle with a really cool blue laser pointer, so why can't we just pick it up and use it? You even let our bullet-sponge date use it at one point!

The turrets from BioShock
Ben "Yahtzee" Croshawhas a good bit about this in hisreviewofBioShock. How can steam-powered weapons know friend from foe, good from evil? Is it something in the walk? Do good guys smell? If they're going to include automated turrets in a game set in the 50s, why not just make them shoot anything that moves? I'm willing to suspend my disbelief that these things have motion sensors, but a moral compass? No, that's where I draw the line.