The indie rock band Ex Cops was invited by McDonald's to play a show the fast-food chain is promoting at the 2015 SXSW music festival in Austin, Texas, one of the preeminent festivals for up-and-coming groups.

The multi-billion dollar corporation's offer of payment?

Zero. Zilch. Nada.

This did not sit well with the band, and half of the pop/punk duo, Brian Harding, responded on Facebook with the group's rationale for declining the gig, an open letter that has since gone viral.