Jiverly Wong letter dated by Post Office?

I thought the Post Office stopped putting dates on mail. I took another look at mail I received yesterday and there is no date on the envelopes. Perhaps they still do it in Syracuse, N.Y., Yes? Curious.

Apr 7, 2009 8:58 am US/Eastern
Binghamton Gunman Sent Letter to TV Station
Excerpt:
The letter was dated March 18, more than two weeks before the shooting. It included photos of Wong smiling with two guns, a gun permit and his driver's license. The envelope carried three stamps: two Purple Hearts and a Liberty Bell.
http://wcbstv.com/local/binghamton.massacre.jiverly.2.977827.html
As always,
BB