No one but no one is going to answer a survey like that every 10 minutes.
I didn't say they had to.
It's the very next sentence after the part you quoted. And in any case the questions about game session length and single/multiplayer seem like they could encounter significant bias just by the nature of the sample pool that's willing to answer such a survey.
Opt-in on install seems straightforward enough for the download. I suppose the applet doesn't really need to be collecting data about the computer it's running on.