I wish I had this problem. The last time a player showed up with anything non-WotC would have been about four or five years ago when I ran a Dragonheist campaign - he wanted to play a sentient skeleton. Loved the idea and ran with it. Totally cool.
But, other than that? Any time I've put anything non-WotC in front of the players, they just turn up their noses. I wanted to use some fairly cool ship combat rules - a bit crunchier than Ghosts of Saltmarsh, but, not a lot. Couldn't even get them to read the pdf, never minding actually using it.
And it's been that way since the 3e days. Hell, even back then I couldn't even get them interested in Dragon mag stuff.