One more note, from an admitted music theory geek...
If anything, Bob Cobert may have been the one who composed the Blockbusters theme at the last minute, since it's just a basic three-chord blues progression. Playing off what Tim said about the last part being "cacophonous"...I wouldn't be surprised if they just told the studio horn players to go ham after playing the melody and sax solo backgrounds, since the arranger didn't have a full chart ready for them. Obligatory "idle speculation" disclaimer, of course.
Strike It Rich, though still sounding cheaply-made, at least has that iii-vi-IV-bvi twist toward the end of the main melody that's more interesting to my ears musically.