You're right that something can be free and abundant and still be of enormous value. I think my point is more that we should think about ways to restructure society around the sharing of valuable abundance.
Scarcity is still there. You can copy adobe photoshop, but you wouldn't be able to build it from scratch in your basement. This is the scarcity: the intelligence, creativity, and man-hours it takes to build it.
You can copy it easily for free now, but the industry will eventually change. Internet is getting faster and faster and eventually (because of the people that feel they deserve software for free), we will only have software services.
I am a developer and I don't create software applications anymore..only services. It's funny because if this wasn't the case, people could buy my apps for a flat-fee. Now they need to pay me money every month to use it.
Also, I pay for things I could have gotten for free all the time. Sometimes this is to reward or encourage the person providing it and then it is called a tip or gratuitity (or sometimes donation, though that evokes charity in my mind rather than voluntary payment for something provided). Sometimes it is because paying for it is just more convenient than going out of my way to get the free version.
[Edit: Slight rewording for clarity]