Cheap plastic toys probably use superior plastic to the PLA plastic of most maker bots though

Pretty sure most makers and tinkerers don't have the liability insurance or budget for safety testing or the mental shielding to handle when their products cause the death of a 18-month-old.

Step one of designing a toy: work out how many children who get it could be killed by it.

Step two: make that number as close to zero as you can.

Step three: arrange for enough money to cover the gap.

Doesn't Toys 'R' Us sell the same "cheap plastic crap" as Amazon?

Amazon sells a slightly different but much wider range of "cheap plastic crap" thanks to FBA. There's no shortage of budding sellers with an Alibaba account who think they have the next best thing (read: re-labeled, generic Chinese crap) and flood the market with crazy cheap products making it difficult for bricks and mortar retailers to compete.

A store like Toys 'R' Us may have a slight advantage when it comes to licensed merchandise, but I think even most of the big sellers long ago accepted that it's impossible to ignore the Amazon juggernaut and now also sell on the platform.

I'm not an expert, but based on casual observation, yes they do.