I've used Avast for years, will continue to do so, but, this caused a heap of trouble for me.
I was installing a separate VPN client (as I believe it is a good idea) just the other day, and was installing lots of stuff from CNET and the likes as I'm setting up a new Mac. It took me a while to figure out (1) what Secureline VPN was and (2) Who installed it (it wasn't me, and I couldn't believe for sure it was Avast - I figured it could be that my new VPN provider worked with Avast or that it was pure malware). And then how to remove it, I just quit it and dragged it to the trash - I hope that's enough.
Anyway, what's wrong with giving the users a choice? A clear message saying we offer a 7 day trial of our new blablabla and then install if the user accepts would have sufficed.
Like I said, a VPN is a good idea, but it also depends on whether you trust your provider or not. Avast so far hasn't showed why they should be trusted above anyone else.