"Why?" you ask. Basic engineering, a personal mistrust of altruism, and "life".
It's basic engineering that adding controls to a system narrows its operating range and makes it more sensitive to external forces. While the stated purpose of this action is "to fight spam", I view it as an added stressor to an overly large pile of political and financial stresses on the operation of the Internet.
Adding controls (or stress) to any system makes that system more brittle and more reactive to outside forces. Drive a system out of its normal operating range and it will oscillate, attempting to escape the stress (or controls) placed on it. It's why large buildings and bridges are difficult to build properly. They have "operating ranges" and have been known to oscillate. End (or end-to-end) controls on a system such as the Internet will make it a very brittle system. You think that the NE blackouts of this decade and the Blaster worm were bad? They were problems in "loose" systems.
It's mistrust of altruism because, somewhere down the line, I believe this "stamp" will shortly become an "income stream". Call me pessimistic but, sometime in the future, some bean counter will suggest that raising the rates to generate more income. Greed has killed more technologies than poor design ever has (yeah, I owned a Betamax).
There's other factors involved. Mostly "life" (i.e., the people that use and run the Internet).
People will never cease arguing. The "pursuit of happiness" involves most of the same motivations that cause people to commit crimes. Profit, power, ideology and emotional satisfaction are the reasons that people commit crimes. It's also the purposes under which business operate. We, as a society, live to argue. Politics, religion, sports, the opposite sex, business, finance, last nights tv show, and so on are all motivations for conflict on a daily basis. That society operates under this load without tearing itself apart should be considered an amazing feat, on a daily basis.
The Internet is no different. We will soon be (or already are) bickering over:
- charging for email
- who "owns" DNS
- IP assignments (I have approx. 4 billion IPv6 addresses assigned to my house) (the assignment is discretionary and, sometime in the future, someone will decide that that's too many and take them back) (I won't be happy.)
- how to protect other people's children (mine's grown and isn't interested, thank you)
- what constitutes digital privacy
- what amounts to digital "fair use"
- and many, many more issues.
Some of the reaons for these arguements are more subtle than others but the justification(s) are nothing new.
The number of arguments will continue to grow in number and volume, each participant justifying/rationalizing their own quest for power or money. Don't think so? There's some today that have declared that the Internet is broken and should be torn down and rebuilt. The only reason to do so is because those people are not "on top". In other words, it's a control issue.
The Internet is not "broke". It's just about the best system that you're going to end up with, no matter how many times you rebuild it. Tighter controls may solve a few short-term issues but will cause problems in the long run. Adding a financial control to fight one problem (spam) will cause another problem to surface elsewhere (fraud?).
In other words, I don't think charging for whitelist membership is a good idea.