Junk mail is worse than e.mail spam as it wastes time, landfill space, and energy. In the 1950's it was characterized as being an incursion, as if someone had the right to dump their garbage on your lawn.
Along with a possible rights invasion and a waste of your time, junk mail also uselessly uses energy, some estimate 100 million trees a year, and other resources to create, deliver, and take to the dump.
I am told that one used to be able to tell the USPS not to deliver it. We would like that right back.
Those who want junk mail can still receive it. We want the liberty to not receive it.