Don't install everything when installing avast free, do a custom install and only install components that you want or need. As far as I'm concerned, browser cleanup and avast cleanup don't fall into that category, there are others. If you have these components installed if you run a Smart Scan then these additional components are very likely to generate these marketing ads.
Rarely do I see these ads/marketing, partly because I rarely run on-demand scans, a depreciated value in a resident on-access antivirus.
Why not use CCleaner from Piriform, recently purchased by Avast Software, use the free version it does most of the things that Avast
EDIT: From your Reply #2 you say that you used the files.avast.com/iavs9x/avast_pro_antivirus_setup_offline.exe, yet your images show the avast free version has been installed and not Avast Pro, which you could disabled ads.