> The moat created by seriously delighting your customers at a young age is large.
I'm not sure that's enough: most kids wouldn't be able to tell a genuine Lego brick from a knock-off.
(Lego famously has insane quality control on their tolerances. But I haven't had any trouble with knock-off bricks so far either.)
I'm sure that Lego still captures virtually all of the revenue in this category, no?