There is a movement afoot to only shop close to home and to buy local whenever one can. It's a wonderful idea - to support community businesses and to help ensure survival of the local farm communities. I love it - right up to the point that it means supporting less responsible companies, strictly on the basis that they have the right zip code.
Some designers only use local printers based entirely on geography. Some will only support local printers who offer paper that has been processed in the country, because of the environmental impact of shipping and sending papers and finished printed pieces - and while I agree completely that shipping = lots of extra carbon dioxide in the air I am not of the opinion that local trumps an environmentally responsible company unless they are also working towards more sustainable practices.
I don't believe it has to be one or the other - local or sustainable. We should call our local printers and ask them if they can print with safer inks every time we send something to print. Let them know what you are looking for, how many pieces you want to order, and what it means to them as far as a lost sale. Really, you are giving them market research each time you talk to them, and if they don't hear petitions for change then they won't feel that pressure to invest in greener technology.
I am sure that your local printing company wouldn't take very long to change their system if they heard from each environmentally minded designer every time they lost a sale. :) And no, of course I don't mean to hound them. Be nice ! Be friendly - and maybe you will be the first person they call when they offer a new type of printing. They might even give you a discount in the future because of all the new business their greener initiatives are churning up. To remain competitive in the future, all printers will be pushed to change from petroleum based inks - and especially now, in the wake of the BP environmental disaster in the Gulf of Mexico - they can generate great PR and look like printing heroes by moving towards inks that require less crude oil and use more veggies.