[neltnerb]

Hmm, I don't think I've ever encountered a website that was broken without enabling javascript that was obviously analytics (I use umatrix pretty aggressively). The one that usually breaks checkout flow for me is that the credit card processors all want to use an iframe and often recaptcha and usually it takes 3-4 reloads before it actually even tries to load it all.

[IYasha]

I've seen a few sites that actually communicate with scripted-in ad providers to verify you have downloaded and watched their ads, visited partner pages. For "free" downloads, for example.