Please tell me where it says either of those things are possible in the rules, and I'll concede you have a point, because those scenarios are indeed rediculous.
However, I don't think it says that.
If a weapon is "one handed" for a creature of size X, it is "light" for a creature of size X+1, and "two handed" for a creature of size X-1 (and so on). It also acrues various penalties for some reason - even if it is a weapon such as a spear or orcish shotput which has no special gripping surface. But the really important thing about the 3.5 rules here is the rule on when you can't use weapons at all.
The restrictions on what weapons you can and can't use are:
You can't use a melee weapon which is smaller than Light or larger than Two Handed. Period. End of frickin story.
So, since for items not listed as weapons, the weapon size is defined as being one handed for a medium creature if it is small, light for a medium creature if it is tiny, and two handed for a medium creature if it is medium - then a medium character cannot use any dimminutive object in melee unless it has been crafted as a Light Medium Weapon.
A bottle has not been crafted at all, and therefore cannot be used for the same reason that a human cannot fight with a Halfling's short sword - it's too small.
Meanwhile, there is no rule about using ranged weapons of any size in 3.5 - which is why you can throw small rocks and kitchen knives (even if it is impossible to stab people with kitchen knives in 3.5).
So yes, you can't hit people with a bottle. It's a light weapon for a halfling, and therefore is too small a human to use in melee. You can fire a Titan's Greatbow, because there is no lower or upper bound on what ranged weapons you can use.
Sorry Count, the 3.5 weapon size rules are completely absurd from the ground up. They don't do whatever it is they are supposed to do, and have no practical advantages at all. If you were hoping to find a way to have less flat absurdity in the game - these rules don't even come close.
-Username17