I totally admit the Japanese versions are superior in quality, it's just that kids don't need morphers totally tricked out so that they cost 50 bucks.
As a kid, when I'm racing out into the summer day along side my friend to take on whatever new threat is attacking the Earth, all I'd really need is a bare bones morpher. Most everything else I could just do in my imagination. I wouldn't feel bad about dropping it, diving and rolling with it or whatever I might need to do while fighting imaginary monsters.
On the other hand, a morpher that costs 50 bucks? **** that! It'd be too much in the first place for an average parent to justify dropping that much cash for a lot of features the kid won't use and doesn't need.
Now ten buck on the other hand... you could get every one of your kids one without breaking a sweat or be too worried that 10 buck has gone down the tube after the toy breaks.
If you're some kinda model collector, that's when it counts the most. But Bandai America is about selling affordable toys for children to play with.