From your link:

> With free software, users don't have to pay the distribution fee in order to use the software. They can copy the program from a friend who has a copy, or with the help of a friend who has network access. Or several users can join together, split the price of one CD-ROM, then each in turn can install the software.

The type of “selling” that GNU is proposing here is exactly the same as asking for donations (and is a misuse of the word “sell”). Since people can resdistribute the software without limit (and someone is sure to put it up on internet), you “charging” for it is the same as asking for donations.

If you don’t like that kind of selling, maybe this is more to your liking? https://www.gnu.org/philosophy/selling-exceptions