And, baseball encourages them not to. Every park has free wifi. They put things up on the jumbotron encouraging you to take pictures of yourself and friends/family and send them in so they can end up on the jumbotron. Modern attention spans are pretty bad but baseball is actively encouraging fans to pay attention to things other than the action on the field. And then they claim it's your fault for not paying attention? How does that work?
Many years ago, only two things occurred at baseball games at Fenway: (1) baseball and (2) the occasional organ solo by the late great John Kiley. No blaring music and promos. No Kiss-Cam. No fakakta mascots. What did people do between innings? They (gasp) talked baseball. Diminished attention spans and the desire to appeal to causal fans created the Horror Show that is the modern gameday experience. I don't know that I blame MLB for this, at least not entirely. They were giving the fans (or more accurately, the customers) what they apparently wanted.
That said, I have no strong opinion on extending the nets. I wouldn't sit behind one. I'd purchase seats elsewhere. So I really don't care either way.
PS - When the nets were recently extended to the dugouts, The Red Sox gave season ticket holders affected a sneak preview and solicited their comments. The results were somewhat predictable. The older fans generally hated it. The younger fans, especially those with kids, liked it.
Donald Trump is a douchebag.*
* In order to avoid confusion and remain compliant with the board's Fair & Balanced requirements, the above statement shall apply to any/all posts critical of any political or otherwise public figures.