IMO ads on a website is far different that serving ads in an application, but maybe that's just me.
Regardless, I have no intention of recommending Etcher with a disclaimer. I will simply no longer recommend it. Everyone else may do as they please. This is just my own personal opinion towards programs that do this in Linux.
Lots of people have no problem with the way Windows and Windows programs treat their users. That is not my way of thinking, I prefer to keep software like this off my computer. In the end you are free to do as you please with your computer.