It would be stupid (but not unlikely) for Hasbro and Mattel to follow the lead of Lego, because they profit from their "exclusive" rights to importing and distributing of their brands to the Major Retailers.
So instead of lowering the prices to match other countries, and being more reliable with their products (to prevent us from resorting to import), they'd prefer to prevent us from importing, even if it meant preventing us from buying products that they don't even import into the country.

It's not like we choose to import to spite them... it's because we have no alternatives on some items (availability), and need to save money on others (excessive wholesale pricing here).