> In fact, lots of confused users asked why Adblock Plus needed this permission and whether it was spying on them. And we explained that the process of blocking ads is in fact what Chrome describes as changing data on all websites.

Sounds to me that the permissions prompt is doing exactly what it should be doing, informing users what the extension can do.

Sure it would be fun if there was a qualified code review process which could gather all necessary permissions from the code, but with bigger extensions this would take days or weeks to get right and unless you can get money out of your extension that is a long wait. Like, I've made couple extensions I've wanted and when I get them done and uploaded I just want to show them off to few friends and install it myself. These are very much spur of a moment things, if I had to wait through rounds and rounds of codereview and questions about my code I probably couldn't be arsed to create extensions.