I personally believe that using closed-source task-oriented (DAW in this case) software isn't that much of a threat to freedom. It does have some cons, but they're not as significant like say, mainstream software products for the mass market that usually connect to the internet for one reason or another, and are mostly indifferent to opinions from a certain userbase. This is especially true for community-supplemented software like Renoise, energyXT, and REAPER.

Just like open-source products, these applications have a tight following. Feedback is often taken seriously and implemented as fast as possible. If you take a look at their changelogs, it's apparent that a lot of the features and bugfixes are results of feedback from users. REAPER's own JS scripting provides a good and open way for anyone to extend functionality.

For most engineers, it's a deploy-once-and-use sort of thing. As such, purchasing a license for a software is basically a one-time sacrifice of freedom. As the code doesn't matter for most of us (at least during the timespan we actually use the product for creating content and earning a revenue), it's almost the same as GPL software when it comes to the community aspect. The only difference is that the community here is supplementary.

No company would mention Linux as even a remotely-supported creature if they didn't care about the userbase.

As for other kinds of applications, I take it as a hardware investment. A very good example is Guitar Rig. I bought it once and never updated it - it still serves me well and it tags along with my outboard gear. I have a number of VSTi plug-ins that I purchased some time ago, and they're still functioning. Before being on a laptop full-time, I had a desktop DAW alongside which wasn't given any chance to connect to the WWW. The entire system is in fact just one big bundle of hardware and software, which in the end is just hardware to me.