Many voices equate 1)the installation of malware that makes the collection of information possible and 2)the actual collection of information. Likewise, 2)the collection of information is equated with 3)processing that information to obtain information of interest are equated. Furthermore 3)processing that information to obtain information of interest is equated with 4)using the information of interest to take action (prosecute or drone strike, for example). Since equality is transitive, this kind of thinking equates 1)the installation of malware that makes the collection of information possible and 4)using the information of interest to take action (prosecute or drone strike, for example). Granted that the situation is a slippery slope, but there is a difference between 1,2,3,and 4.
There's a difference between: 1. The government making a copy of your house key. 2. The government using it to enter your home. 3. The government looking around once it's inside your home. 4. The government using knowledge it gains from looking around your home to prosecute you. These may be true, but it's not a reliable or meaningful difference, especially when the public justice system has no influence on how far through these four steps the government goes. The fourth amendment exists for a reason, and the NSA's hand to god that they won't abuse their power really means zilch once step 1 is achieved.
We are not protected by limitations we put on the nature of our government, but by limitations on its behavior. Importantly, limitations on behavior must exist within the realm of scrutiny. Limitations on government behavior that are beyond scrutiny are essentially just limitations on its nature. 1-4 are essentially the same when they exist beyond scrutiny, which is currently the case with the NSA.
I think the real issue is that most folks don't exactly approve of 1, much less any of the following, regardless of what the motivation is for authorities and if they are, in fact, having their information processed for any myriad number of reasons. That's why much of the hullabaloo over data collection is framed as a privacy concern. Your line of thinking lends itself to the argument I hate the most, which is "If I'm not doing anything wrong, should I care that my data is being collected?" I know there has always been issues with backdoors and talk of what the actual goings-on has been and a bunch of conjecture, which would be subject to the "slippery slope" argument as an objection or call to reason, but the revelations as of late have just shown that the slippery slope is actual being slid down by NSA, CIA and the like. Whether or not your information collected is going to be collected, information obtained from it or acted upon doesn't seem to be the case, essentially because it would seem that automation of all of these steps renders 1-3 the same thing, because of a lack of jurisdiction or oversight. As for 4, well, I mean, the ball seems to rolling in that direction already.