The Black Hole Bar and Grill is located on Grand Central Space Station. Its only known bartender is J'oh, who can mix thousands of different kinds of drinks, but (like most of the patrons of the bar and residents of the Station) has no tolerance for robots. It has a convenient airlock, for ejecting "rust-sucking scrap-heaps".
Marvel comics continuity
Landmine and Cloudburst, on a mission to buy microchips at the Station, stopped in at the Black Hole for a drink (and presumably to look for a chip broker). They witnessed J'oh refusing to serve a Chromite, and Landmine attempted to stand up for the robot (much to Cloudburst's chagrin). An Urtuskian accused the "human" of being a robot-lover, and the already tense situation quickly erupted. In the ensuing brawl, the Chromite was ejected into space, and the Autobots were defeated. J'oh allowed them to finish their drinks, however.
The Autobots later returned to the bar in an attempt to pay Berko's tab. Unfortunately, the Nebulan Powermasters Hi-Test and Throttle had tipped off J'oh that the two were robots in disguise. J'oh and the crowd summarily ejected the two into space.
While it is not made absolutely explicit, it seems clear that the Nebulans, J'oh, and the Mecannibals have an arrangement whereby J'oh arranges for robots to be thrown out the airlock, so that the Nebulans can then stun them as they drift in space and deliver them to the Mecannibals to be eaten.