New Alliance initially released Bonus Fat as an EP. In 1987 New Alliance was sold to SST, who re-released Bonus Fat on EP, cassette, and compact disc. In 1988 SST paired Bonus Fat with the band's debut album Milo Goes to College as Two Things at Once, a single release compiling all of the band's recorded output from 1979 to 1982.
Ned Raggett of Allmusic gave Bonus Fat three stars out of five and focused his comments on "Ride the Wild" and "It's a Hectic World", calling them "gentle, surf-inspired power pop more than anything else." He noted that "It's a Hectic World" is "even more explicitly surfy in ways, but with a nervous, flat new wave edge to it as well — not quite Devo if they grew up on the coast, but there's something to that comparison." Jenny Eliscu of Rolling Stone remarked that the inclusion of these two songs "can't be considered much of a bonus." Rock critic Robert Christgau similarly called these two tracks "forgettable [and] surprisingly poppish" but gave the compilation an A- rating on the strength of the Fat EP material, which he said sounded better on this release than on the original EP.