ixtab, there is a world of difference between being concerned about your privacy being eroded and registering an ereader.
Incidentally, I'm in the UK and was happy enough to register my Kindle. But if I wasn't planning on buying books from Amazon, and was happy to live without the ability to have collections, I can very much see the attraction of not registering it. There doesn't need to be anything 'dodgy' about it and from my reading of it no one has made any such suggestion until very late in this thread saying we shouldn't do so....
Edited to add.
This is much more concerning than having my Kindle registered: bbc.co.uk news story -
Email and web use to be monitored under new laws
I know it's April 1st but....