I think what robostwantdata was suggesting was that people would supply a "Use my mechanical pen for a fee" type service, where customers send the text they want written and the address they want the letter sent to.

As I've already said in my direct reply, there's still the various costs involved in posting the letter, and if the community is based on a particular geographical area e.g. "Connacht Hill Farmer's Association", then it would raise eyebrows if the envelope had a Kazakhstani stamp on it.