In No More Heroes, Pizza Butt (as it was known at the time) is the subject of a small series of Assassination Gigs that Travis Touchdown takes on from K-Entertainment. Pizza Butt has only just began in Santa Destroy, and for unknown reasons K-Entertainment is issuing a mission to assassinate the CEO, presumably the father of the Batt family. The jobs continue later on with two more missions involving killing the replacement CEOs, presumably two of the brothers of the Batt family. Both Travis and the player deal with these as little more than filler jobs.
In the three years between No More Heroes and No More Heroes 2: Desperate Struggle, Pizza Butt comes to be under the management of the third brother of the Batt family, Jasper Batt Jr. The name is changed from Pizza Butt to Pizza Bat and they establish a bat logo, presumably so they can be taken more seriously, and in the absence of Travis taking on assassination missions, they grow exponentially until they become one of the most powerful forces in Santa Destroy, opening a massive mall and base of operations across the street from the Motel "NO MORE HEROES". As revenge for the deaths of the previous three CEOs, Jasper hires the Quintet to murder Randall Lovikov and Georgy Bishop, some of Travis' best friends, as well as allying with Skelter Helter. This motivates Travis to climb the ranks of the United Assassins Association for the second time, eventually killing Jasper and presumably taking down Pizza Bat for good.
Heavy thugs in Desperate Struggle eat Pizza Bat pizza while idling around during Ranking Battles.