Postal

The Post Office has selling more than 30 million "Forever Stamps" per day for the past several weeks, as we get closer to the next rate increase, which is only 1 cent.

I don't get it though - if everyone buys the Forever Stamps, and they keep buying them, won't the Post Office go out of business, (or whatever government entities do that really aren't businesses) in a couple of decades, if not sooner?

If they're saying they can't operate at the rate that the current postage provides them, then how can they say they will be able to continue to operate at that rate forever?

Will someone explain that to me?