Yeah this is not a fun one, I have done repairs and now do retail this issue is insanely common. Pretty much all budget laptops have this threaded into cheap plastic and I have had many customers devices hinges fail within 4 months in retail.
From what I can tell you also got quite lucky the hinge snapped on the base and not the screen. I've had a couple customers unlucky enough to have it snap on the screen and shatter the glass and or LCD.
The cases where it doesn't completely destroy the screen or base you can normally use epoxy glue, melting or something similar. But that still is normally a temporary solution it will probably break again. If that can't be done or a more permanent solution is needed, I've found that repairs with a metal plate and bolt seem to last I've also seen some people just use an L shaped metal bracket and not close the laptop again...
Regardless its a really annoying thing, I try to purchase and recommend devices with Metal frames (base and screen). Unfortunately even mid range laptops are now following this trend of plastic screwed hinges.
No I think its just cheaper, if it was stronger you normally would have a metal plate or the entire base would be metal. The only time I have seen those fail was actually the hinges themselves and not the attachment points. If the metal plate or base somehow got severely damaged I doubt it would cost much more to repair and its still unlikely to damage anything else.