Out of curiosity, what form of "spying" do you think is enabled by Javascript that would not be possible without Javascript?
Edit: And since I replied to a small part of your comment, I should say that I disagree completely with your "few people truly care about their craft" statement. At least, I think that writing code that handles a lack of Javascript is only valuable if you have enough users to justify it. i.e. if you spend 20% of your time working on features for 0.1% of users, then you are doing a disservice to the rest of your users. Even more so if you have to compromise the experience for everyone else such that degrading is an option.
In some cases, you go out of your way to accommodate small fractions of your audience. ARIA and catering to those with disabilities is a good example. But turning off JS is a choice; one I respect, but feel no obligation to cater to. I think pages should show a noscript warning, but other than that, its a matter of engineering tradeoffs.
Some analytics companies track mouse movements to watch how people interact with web pages. They can also use JavaScript to fingerprint browsers beyond what is available with cookies.
Edit: And since I replied to a small part of your comment, I should say that I disagree completely with your "few people truly care about their craft" statement. At least, I think that writing code that handles a lack of Javascript is only valuable if you have enough users to justify it. i.e. if you spend 20% of your time working on features for 0.1% of users, then you are doing a disservice to the rest of your users. Even more so if you have to compromise the experience for everyone else such that degrading is an option.
In some cases, you go out of your way to accommodate small fractions of your audience. ARIA and catering to those with disabilities is a good example. But turning off JS is a choice; one I respect, but feel no obligation to cater to. I think pages should show a noscript warning, but other than that, its a matter of engineering tradeoffs.