Public service announcement: If you find yourself at a Smash Mouth concert in 2015, and you’ve brought along a loaf of bread to snack on, do not throw a piece of that bread at lead singer Steve Harwell. He really doesn’t like that.

During the Taste of Fort Collins food and music fest in Colorado, fans — or at least, people willing to listen to “All Star” — starting tossing slices of bread in the air, likely the same bread being given away for free from one of the festival vendors. Some of it landed a bit too close to Harwell, who erupted in a long stream of profanities and threats. The crowd booed and he huffed off stage. Maybe he’s gluten-free?