Economics is a bullshit "science" based on choice and decisions made in board rooms. The price of wood is up because it is a wall street commodity. I live in timber country and the mills have be FLUSH like I've never seen in my 10+ yr around them. There's no shortage of anything, so don't buy that rap.
Look for comments made by the CEO of autozone, who recently stated something to the effect of " although our costs ate going down, and profits up, we won't be lowering prices because people are willing to pay these prices." Its the same with everything and the whole "people are willing to pay" makes as if we have much of a choice. Sure, you can say we have a choice to not buy things, but I beg that, thanks to intense marketing psychology/propaganda most of us have been hardwired in a way that makes shifting a lifestyle like beating an addiction.
Gas is 6.90/gallon where I live in California. My 15 yr old subaru gets 18mpg and I've gotta drive 45 miles round trip to work. Costs me close to a hundred bucks per week to use my car. I have a choice, right, I could ride my bike or something, stay home more, etc when I'm not going to work. Just like if I can't afford a deck that's gone from $54 to $70 in the past 3 years, I don't have to skate.
Was the whole 52.50 deck with grip sustainable? I have no idea, but this rant stems from the notion that commodity trading and economics is a can of bullshit that has always and will always degrade the quality of life for all beings.