Why would it cause that?No you can not. The "it" in this case would be adding mechanical crunch to provide hooks for an EWP type set of weapons to be distinctly useful without dumping their weight on the gm or being overly good. That crunch would almost certainly require itself to be extended through most monsters, some feats, some spells, some class abilities and so on. That is not a small task or something that can be retroactively added through a bolt option.
5e's overly simplistic design ensures that there is no room to "do it" without impacting those other areas. Your examples look to be treading into the realm of obviously better mechanical nonchoices & that was one of the design failures I mentioned would be imposed by a shallow design space
One of the options is to make exotic weapons balanced to martial weapon or regional weapons.
So there would be no difference from not finding greataxes in the halfling village.