Knives in Resident Evil

Why are the knives so ASS in the early games. 

I've been playing the original RE1 to try and get used to using tank controls and I made the mistake of trying to kill a zombie with my knife (even though I know they are useless) and I died so quick. It's so frustrating when I run out of ammo because it's almost impossible to kill them with the knife without haemorrhaging mass amounts of health so I end up trying to run around them and getting bit anyway. 

When I was playing the RE4 remake I barely had to use the knife except for parrying (which is so helpful) but at least they are easier to use with modern controls.

Anyone else have knife problems with the early RE games?