I wouldn't extrapolate the the level of immaturity it takes to make that connection to whoever named the service. The last time I giggled at hearing the word butt as part of a larger word or phrase was probably the second grade (cigarette butts, pork butt, etc)
Given the history of SSB, it seems quite unlikely that's the case. Originally developed by and for someone living on a boat, they used a nautical term to name the project.