I don't know if this is relevant or not (I can't remember the original
question).  But the muffler shop sculptures may be like the tin men that
Sheet Metal Workers make.  Tin shops and HVAC companies often have them as
oudoor signs.  I gather they are a union thing.  You can see them in Labor
Day parades, and constructing a tin man is often a sort of fun final
exercise before graduation in SMWIA apprenticehip programs.  Whether they
are originally folk art, advertising, or entertaining exercises of skill,
some of them actually do make the jump to museum pieces.

--Mark