Let me intervene here: the fact is that this IS bad, but it is ANOTHER TYPE OF BAD, not "spyware" bad. One analogy could be if you correspond "spyware" (sending information unrelated to the function of the software) with theft and DashImbroglio with assault. Both are bad, VERY BAD. One is bad for one reason, and the other is bad for another reason.
Spyware is a class of malware that causes lot of trouble. It is usually used to get your home banking passwords and other stuff that generally cause lots of monetary damages.
The Dash Imbroglio is an instance of another class of malware -- that deceives the user, that AT THIS POINT IN TIME, unless you advise and ask for permission first, will reasonably expect it to be just a local search and instead will do an Amazon search in addition to it.
The solution is simple: before sending any data to amazon, the first time the dash is used for each user, it should show a simple dialog stating "hi! Amazon contributes for you to have this wonderfull and Free software! How about contributing back and letting it see your searches, in case it wants to show you some offers embedded in the results? [Ok] [No, thanks]". The default could even be "ok", but no one would be DECEIVED -- the operative word that makes RMS be at least partially right.