Pressure is pouring on baristas at a popular Chinese coffeeshop because of their demanding customers.

Manner Coffee (MC) outlets were the scenes of a recent altercation between impatient customers and overwhelmed staff, Global Times reports.

Patrons apparently blew their top for waiting too long for their orders. At a Shanghai outlet of MC, a client lost her cool and threatened to file a complaint against a barista.

The MC female staff member, seemingly overwhelmed, lost her composure and poured coffee grounds on the face of the customer and dared her to file a complaint, Global Times reports.

In another MC outlet, a staff suggested to a dissatisfied customer that the order be canceled, triggering a shouting match and brawl. Police reportedly intervened and the two were pacified.

Manner Coffee issued a public apology last week over the incidents.

It’s not only delayed order that triggers coffee clashes.

In Seattle, USA, a drive-in male customer complained to the female barista of a coffee stand, sparking a heated exchange that was caught on camera by a bystander. The video that went viral on social media shows the customer arguing over the $22 he paid for a cup of coffee.

Emma Lee knew the regular customer but was surprised that he was complaining for the first time about the price of her coffee despite being indicated in a menu sign.

The video shows the guy getting out of his car and throwing the ordered coffee into the store window counter.

As he was driving off, something struck the car’s windshield.

Lee is shown on the video striking the car with an ice hammer, leaving a crack on the windshield.