Etsy Flooded With Chicken Jockey Merch After Insane 'Minecraft' Trend

"Minecraft" fans have been going absolutely ballistic in theaters thanks to a wild new trend that's even resulted in at least one police response ... and now some are trying to cash in!

Here's the deal ... "A Minecraft Movie" -- the video game film starring Jack Black and Jason Momoa -- has some teens going nuts ... trashing screenings when a baby zombie rides a chicken, AKA "Chicken Jockey."

Several videos have gone viral of crowds going berserk -- throwing popcorn, screaming, running, blowing airhorns, tossing confetti and even bringing in a freakin' live chicken! -- and now Etsy shops are getting a piece of the insanity.

The e-commerce company has been flooded with chicken jockey gear this week ... which includes people selling shirts, cups and toys.

Of course, it's assumed no one's REALLY that excited about the scene -- it's just a social media trend for clicks ... and it's been working, with the antics making national headlines.

The teens might think it hilarious, but theater officials are getting pissed ... 'cause not only are huge messes being left behind -- there are patrons there to see the movie who don't want the buffoonery. Some theaters have put up signs saying the madness won't be tolerated.

In at least one instance ... cops were called when a go-up went total apes*** for chicken jockey -- a result the film's director Jared Hess told EW was "bananas" and "hilarious."

Despite being brutally panned by credits, 'Minecraft' had a huge opening weekend ... so it's a safe bet the chaos ain't stopping anytime soon.