As in itinerant singer, he might have violated various local ordnances, including vagrancy.

Singing a bawdy song wouldn't have helped him. Presumably the song came up at the arraignment.

And yes, the standard version with the unspoken sex and illegitimate kid was at best borderline in many places in the U.S. at the time. And a tiny rural community like Mona, in Mormon country, would have been most unlikely to countenance it.

Especially from, well, a hobo.

The uncensored song was still considered "bawdy" into the 1950s.