The price of copper has skyrocketed, and it's not an all bad thing. There are great alternatives to copper when it comes to re-piping your home, so there's no real need to pay any premiums there. But why not take advantage with the old copper pipe you're going to replace?
Scrap metal recyclers in Seattle, where I am, are paying upwards of $1.75 or so per pound for scrap copper. This is what they'll pay you for what you'll probably throw away anyway. Why not take advantage? If you're lucky enough to have all your waste lines in old copper pipe and plan to gut the house anyway, so much the better. Once you get higher than 1-inch diameter pipe, you'd be surprised how heavy that suff is. The smallest waste lines are 1.5. Ka-ching!