Not understanding how a bunch of adults could be interested in a motley gang of spunky children and their otherworldly problems, studio after studio shot down the mega-hit, believing the mixed-aged cast was too confusing for audiences to get behind. Yes, Hollywood thinks everyone must be exactly as narcissistic as them.
Those who were willing to give the show a shot offered to accept the series on one of two conditions: Either make it a children's show, thereby killing the central mystery of the plot, or cut those crazy kids altogether. The show already had a character adults could relate to, the networks thought. Why not make the whole plot revolve around Sheriff Hopper investigating paranormal crimes from week to week? That would work, right?
The creative team behind the series, the Duffer brothers, held out for a network that would give their show the treatment it deserved, and eventually found a home on Netflix. The series got to keep its plot and cast intact, and we got a great series commercial-free. So, win-win.