So many apps would require internet that users would become desensitized to the permissions box and just say "yes" every time the box comes up without even reading it maybe?
That will happen anyway - see iOS where users nearly always accept permissions, or Windows where users just click OK.
It's not the frequency or importance of popups. Users simply don't read them. From watching users, the users who don't read them usually have an image in their minds of what they're trying to accomplish and an image of the screens they need to go through to get there. Any popup or notification screen is instantly dismissed so that they can see the screen behind and try work out if it's where they expect to be. It's maybe 25% of users who do this, but they do it constantly regardless of what the popup is.
Allowing Internet permissions by default is one thing, not providing a way for the so inclined to disallow them is another. I think most people would have no problem if this was just a changeable default.
