Because there is no proof of said activity.  
Since it wasn't being reported I did some research.  Did you know the 'electronic voting machines' in Wisconsin aren't connected to the Internet?  They are electronic in their vote tallying only.  Similar to a high school SAT test.  It's impossible to 'hack' a machine, much less hundred of them, that aren't connected to the Internet.

This is literally headlines being drummed up by people that like to to stir the pot.

And I'm not a trump supporter!  I am however, an intelligent human being rather than a mob follower.  Let's put this hacking to rest.