While I don't support the liquids rule at all, as I think the premise is flawed, I can understand (to some extent) why the rule is written (and enforced the way it is).

They are trying to eliminate judgment as much as possible from the equation. So, they make the rule as straightforward as possible - 1 quart or 1 litre zip-top (not Zip-Loc, which is a brand) bag, 3 oz or 100ml of liquid, gel, etc. per container in the bag, no exceptions. I think this is in recognition of the capacity of some of their employees. If you give them the responsibility to apply judgment, they are bound to use it improperly.

Unfortunately, much of the traveling public, (and believe it or not, even some of the TSA staff) who can exercise judgment, see the ludicrous results this sometimes generates. Some our willing to exercise judgment even though the powers-that-be would prefer they didn't - others don't.