In addition to the line-ending rhyme in the song, there's internal rhyme in the line "His records sell extremely well, but does he really want it," and this poetic excess gives some indication of the character's success. (The internal rhyme is part of the structure, however, and not unique to this particular line; it's also in the line "It's not the way he wants to play; he does it for a living" in the first verse.)
There's alliteration in the line "But no one knows just how he feels as he cuts his comical capers," and the artifice of this device mirrors the character in the song, who is putting on a façade and doing something other than what he actually wants.
