Users don't really need webfonts; text just needs to be readable. And they don't need to grab jquery from a CDN; it can come off the server. Heck, they don't need to grab anything from a CDN--the app server can serve images just as well as Cloudflare.
Do users really need DDOS protection? No, that protects the server, not the user. And it banks their legitmate request--needlessly--through a proxy server, which certainly adds latency. Not to mention that Cloudflare can see everything they're browsing.
Do users need single-page JS apps at all? Why not just render HTML4 on the server like in the good old days?
So why do developers use these technologies? Because it makes the user experience better. And so do analytics. Without analytics, developers are flying blind. And no, Apache/Nginx logs don't capture the same data--especially with more advanced JS-heavy sites.
Users want websites that load fast and are easy to use. It is impossible to build or improve such a site without data upon which to base decisions. That's why analytics are a necessity.
The use of bandwidth is a moot point. If advertisers hadn't abused the user's good will we wouldn't be where we are today, but there's no putting the genie back in the bottle.