huh? you don't need to stop flashing thirdparty router with 'more' functionality with the default firmware, what you need to stop is /not/ change the default password, as that was the attack -- if you have a sensible mind, you'd change the password of anything with a password...
that article is quite misleading (misleading in a sense that this is not the norm), as very few in their right mind would not change the default password *AND* open turn on remote management... that actually would difficult to do both for novices, so it must be intentional (or some youtube tutorial instructs users to do this)
I think most (if not all) users that flash thirdparty firmware are competent enough to change the default password.
EDIT:
Now that I think about it, most likely these routers are sold as is (remember those Tomato-based routers from CDR-King?), then the one scanning for these routers are the one that sold them... (conspiracy theory mode activated

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