Fixes a bug where an invalid item may be compared.

Ran into this issue while going through the tutorial causing the game to segfault. A 9mm casing from the Uzi was being generated. When looping through the possible points to check if any existing items will accept charges, it'll incorrectly only use items on the center point. If another point contains more items then the center, it'll dereference a non-existent object.

Also removes a comment for a parameter that no longer exists.