>they would be able to watch you walk around the store on CCTV

That seems like an unfitting comparison. The problem doesn't arise in the store, but when using the product at home. The equivalent of store cctv in this comparison would rather be a server log on the Mozilla website (where people get the product). It's fine to do telemetrics there without me consenting (as long as it's only used by first party) if you ask me. But after I leave their premises it's none of their business how I use the product.

Sounds like you want it to be ok that your newly bought pack of condoms sends out a message to the factory once you open one.

Yes. Otherwise, would you accept your home/apartment to have telemetry so that the home builder knows what rooms/features you use or not?

Software isn't a house. It's also not a car or whatever your favourite other analogies are.

Software is often described as "tools" and so an analogy to a drill or a magnifying glass is as apt as any. In fact a car is a good analogy to a browser because we use browsers as sort of a "second home" in our computer and it allows us to "visit websites" and a browser is a whole ecosystem unto itself.

So if software is a tool and my drill is monitoring the holes I make in stuff and its efficacy in doing that, that seems fine, but if the drill is sitting in my toolbox being a busybody and sending back everything it can find about me from within the toolbox, that drill is made by assholes, don't you agree?