Anyone is free at any moment to define:
interface operator (.foo.)
! ...
end interface
And it has been used in a smart way in a couple projects I have seen. Therefore, sadly it seems that dot would be hard to implement in a way that does not clash with custom operators.
% sucks a little bit, you know what, in my opinion, sucks a lot? Inability to do this. While percent is an aesthetics issue, the other largely limits usability of the language.