No, because it'd be too much like another Flckr/Photobucket scenario: "Sorry, this image has been set to 'rivate' and is only viewable by [X]'."
Now, to make the entire deviation page viewable only to those who were invited, as on YouTube, that would be a different story, because:
(a) It wouldn't mix in with the publicly-viewable deviations while browsing (b) On other websites, the thing wouldn't show up, which is better than having the aforementioned quote plastered all over the page. Besides, it wouldn't throw the rest of the page's HTML into a mess, thereby making said deviation less harmful than Flickr/Photobucket's harebrained way of doing things.
it's common sense to allow non-deviants to view this site. i have a lot of friends and family who check my profile, it would be silly to ask all of them to make a profile just so they can see my works. besides, the watermarks are a good enough protection against art theft, in my opinion.
I find it kind of ridiculous that if you disable the feature, anyone that wants to see your work must register do deviantART. What if you just want to show one of your works to a friend via MSN? They would be forced to join dA. And those who don't have a personal art site outside dA, how would they show their future jobs?
The artist should have the choice to turn these off. The choice! PERIOD! Choice, it's not a new concept... choice n. The act of choosing; selection. The power, right, or liberty to choose; option. Thank you!
I believe that there should be a 4th option - and that would be that Sharing be disabled, but non-members of the DA community should be able to continue seeing what they've come to DA to look at, or else DA will most certainly have more non-artists than ARTists and last time I checked, this was DeviantART not DeviantSPACE or DeviantBOOK.
It shouldn't be all or nothing, there should be varying degrees of public and private - so that we the members can have a choice of how distracted we want the people looking at our art can get by all the other crap on the page.
I think there should be an option to opt out, if the deviant so wishes, but I'm not too sure the 'all or nothing' approach is right. Don't think disabling the share buttons should make the deviation invisible to the gen public unless that is also personally desired by the deviant (as others have stated, more eloquently, previously.....).
I'm game. But I think providing the option to "opt out" to those who want it is a good idea. Even if it's not the best option for people if they want exposure, it gives the feeling of control. Above all, that's what people want, the feeling that they control how their work is seen (even if it's really more of an illusion of control.)
If some one wants to steal art they will find a way no matter what buttons are used. I wish this was more understood than it is. If I would have blocked my art to just the members of this site I would not have had an email asking to use one of my photo's in a book.