Another thing that they did a while back (I think it was last year), was to stop issuing actual checks. You have 2 choices now....direct deposit into your bank account or you can receive a pre-funded debit card if you don't have a bank account. (kind of like a gift card)
The reason of this is simple. Think about the gift card you got last year for your birthday. Did you spend all $25 dollars at Outback or was there a few cents left over?
Now take those few cents and multiply by a few million people who receive those Social Security cards.
The government now gets to keep quite a bit of money on it's books, rather than in the hands of those who it belongs to.