If you wish to stay anonymous, you can invent a name to use, as long as the postman will deliver it. Estimates are at 20,000 to 50,000 new users, every day, with thousands of those joining the actual internet. Good luck to everyone that tries. No catch, that was it. You will now become part of the Mail Order business.
Many large corporations are happy to pay big bucks for quality lists.
Next, place one card into each envelope. What you are doing is creating a service. Look at it this way. You do not need to re-type this entire letter to do your own posting. This will copy the entire letter into the computer's memory.