Remember Firesheep? It used to be the normal thing to use plain HTTP over open wifi networks. Literally anyone else on that access point could read your whole network session, cookies and all. https://en.wikipedia.org/wiki/Firesheep

Firesheep and Snowden are the confluence of factors that happened around the same time and led to the current near-universal use of HTTPS.

There was also an fun Android app which you could use to replace all YouTube videos with a different one