Dixie
You make some good points, better than Chuck's actually... good walnut has always been relatively expensive, but like most natural resources, tastes dictate a lot of what happens and walnut is not an exception. In real terms walnut has been getting cheaper for the last 8-10 years... the reverse is what truly happened, plastic stocks got cheaper, a lot cheaper... <img src="/ubbthreads/images/graemlins/frown.gif" alt="" />
That is not to say that the best walnut has not gotten much more expensive, just straight-grained walnut that dries and machines easily.
Temperature does introduce another potential accuracy problem into the equation, but no worse than wood.
As for sealing the wood, the finishes used by the manufacturers are nothing special as water sealers. Trying to get a thin enough layer under a butt pad to seal and sit nice and tight against the stock is tough business. Dings and cracks in the finsih coupled with pores built into the finish by the evaporating solvents leaves them pretty susceptible to sucking up water.
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