Goes to show that book smarts and survival smarts are not the same thing.
Depends on what he planned to do with it. Most people don’t generate any remotely interesting data most of the time. I might give them the same deal, of course after the first month when the thing didn’t even get turned on (unless my twice a year “crap I wish I had a cellphone” usually related to a flat bike tire occurred that month) they probably would have kicked me out of the study. But if you really don’t care what they find out about you what the hell.