Quoted from CrazyLevi:

It could confuse location players, who can sometime barely grasp the most basic concepts of pinball.
It would take time away from developers' more important tasks.
It's pointless. Previous attempts at "offering new ways" to play have failed. I'm sure Dredd's "Supergame" wasn't just intended for use in one game.
I really wasn't aware that so many of your were passionate for co-op pinball. It really seems like something most would try once or twice and never try again. One of those attempts would be to force family/wives/kids to play a co-op game with you, which they may do to humor you, before going back to whatever it is they'd rather be doing. I can't argue with you though, If you like it, you like it. You have to convince the manufacturers it's worth their time, rather than convincing me it's a fun idea.

Quoted from CrazyLevi:

What you should be doing is pitting your daughters against each other in a battle royale for their father's approval.