Another take on this issue is that the FBI and NSA have a strong opposing interest. While they may not lobby in the same sense as Apple etc., they do represent law enforcement, which is an enormously powerful lobby in the US. So all those private companies are on one side, sure, but US law enforcement is on the other, and that's quite a fight (and one that law enforcement has been winning for a long time now).
But what is it that makes law enforcement a more powerful lobby? The average cop with several years of experience makes significantly less than an engineer straight out of college.
