Why did Zenith's cabinets get cheap, and why?

[drh4683]

That '68 zenith colonial console I picked up this past saterday is much cheaper. All that colonial "woodwork" on the front sides and bottom of the cabinet is molded plastic! Even in '68! The woodwork on top of the cabinet and the sides is real wood though.
In that same TV, zenith used plastic angle braces to reinforce the cabinet from the inside. Most sets used the triangular cut pieces of wood to do this.

Ive seen alot of cheaper zeniths with photofinished cabinets, beginning around 1965 model consoles. They used some kind of composite board, not wood though. Alot of times, heavy things got placed on top of the set and you can see it cave in and in most cases, a permantent dip can be seen on top after prolonged support of a heavy object.