You're absolutely right. The result usually is though that the kid finds a toy they like then puts in on their Birthday/Christmas wishlist from where the Santa buys from Amazon. I like to think I never do this, but if the price is much higher even I have a limit.
I think that manufacturers should sell to physical toy stores at a lower price, and actively make sure online price is the same or higher than instore. but I dont how easy this is to police or even if is legal in some countries.