I'm all for OSS too but when it comes down to it, if you're serious about video editing, this isn't really a tool you can make compromises on (and trust me, I spent a lot of time trying before pulling the trigger on buying Camtasia).
This is after having recorded about 50 hours of real-time video over a few years. There's just so many things you absolutely need to be happy and productive when recording -- especially if you plan to do this for a living.
Using a bad video editor (and I'm not saying Shotcut is bad because I haven't installed it yet) is just a really draining and time wasting experience.
It takes me around 70 minutes of real life time to produce 10 minutes of video after years of work flow optimizations and using what I think is one of the best tools available to make screencasts. Almost all of that time is spent editing in Camtasia (stopping and starting the recording, correcting mistakes, adding post-production effects, etc.).
I would love to switch to an open source tool (for many reasons) but the reality of the situation is, I wouldn't switch unless it was remarkable because it's such an important tool if you're livelihood depends on making videos.
And there are way more video recorders than people on earth, lots of people want to create videos from their children, family gatherings, vacations etc. if only they knew how.
There's an awful lot of people who want to break into Youtube with no money.
There's also a small but well-represented on HN market of people who want to have an OSS/Free Software only workflow.