I tend to agree with Luke Delwiche's contention that letterboxed
commercials are designed to entice the viewing audience into believing
that the ad is part of a theatrical trailer for an upcoming film.
To that thought, I might add that the advertisers are gearing the
letterboxed commercials to the same younger demographics that frequent the
movie theaters.  If you "hook" that younger audience into believing they
are about to see a preview, you might keep them for at least part of the
advertiser's "message".
It all comes back to dollars and cents......and any device one can think
of these days to keep a viewer's finger off that remote button.
Brian D. Mudd
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