I don't use it because:
A) People say it's broken with construct, or doesn't work properly with it, and there seems to be very few using it fully.
B) I've never been a fan, from way way back when I was very anti-anything involving code, it always seemed to me like comparing BASIC to C++, and Python didn't seem powerful enough in the long run to warrant the effort required to learn it (like the effort required to learn how to drive a manual car in the UK, when you fully intend to move to the US and only ever drive an automatic heh). Even though since teaching myself PHP (born from a case of "if I want it done properly, do it my damn self, lol"), I've heard it's surprisingly similar to that and Perl. But it does (to me) still seem to have some kind of stigma attached to it.
C) I've yet to find a reason to use it. But if it could do something I needed to do, which events couldn't. I'd use it... and bombard the forum with "but can it shoot lasers and make spells?" posts
But seriously though, given a choice I'd rather use events over python, or any kind of language for that matter. A case of path of least resistance (python would require I learned how to use it from scratch). Though if I saw real world examples of what python could do, that events couldn't (or made more complex), I might be more open to it.