A URL may become invalid

Internet distribution was thought of when the GPL 2 was written, the reason that it is only allowed when the product is distributed via the internet is because there is no guarantee that the URL will allways be valid, and that the data at the end will always be the same. The latest GPL licence that was finalised last month contains the same provisions. Both version of GPL has been very carefully thought out, and all the clauses in it are there for a reason. If Skype did not intend to follow the rules they where free to use other technology.

If Skype wanted to save the cost of pressing a CD, they could have put an offer on that flyer for a free CD to be posted to anyone who asked for one. As hardly anyone will ask for one the cost to them would have been negligible.