Different target customer, the 11 isn't a performance binding. That customer is more likely to need a little 'nudge' to get from the trunk to the backseat. The 12 on up are designed for skiers that either are not in the backseat or are skilled at skiing from there.
It's not a conspiracy.
Huh. I haven't heard/seen this perspective before. Yet another hidden "gem" (or, rather, confounding and confusing and non-intuitive factor) added in when you decide to buy a binding with a particular max DIN.