In contrast to other Android licensees faced with the potential of competing with preferential Motorola treatment (treatment Google denies will occur), Windows Phone licensees are competing with preferential Nokia treatment since only Nokia has the freedom to customize Windows Phone 7 as it sees fit.
Most adults don't want to shell out the cash to buy their kids a phone, nor do they want the kid to suddenly have all the freedom opened up by their own, unmonitored phone line.
Smartphones do provide a lot of freedom, but they are still controlled by phone companies, and in some cases (notably Apple's) also by the manufacturer.
That moment they light the fuse under your ass it's a sense of total freedom because I knew then nobody could get me out and no phone call could modify what I was doing there.