I just registered as a forum user solely to echo this complaint.
Like most of your users, who tend to be rather computer savvy, I fully understand the need to subsidize your free offerings (although I'd point out that if your paid downloads aren't doing the job, there's a problem with your business model or marketing). But the AVAST app is clearly deliberately coded to skirt detection by Unchecky and then installs itself in a hidden, or at least nonstandard, location. Moreover, I have to download an uninstaller from AVAST and then restart my computer in safe mode to uninstall it?
This is underhanded and beneath a company of your industry stature, and it calls into question the integrity of even your paid offerings.