If so, will these same bashers ensure all their other web traffic goes no-where near China?
I can say authoritatively that the US DoD ensures that quite intensively. Of course, that doesn't stop China and Russia (at least for 99% of breaches) from using a VPN far away from their nation, then hijacking another compromised network to compromise a US DoD network.
As for purchases, everything that's purchased has a specification book and purchased products have representative samples examined in depth, destructively at times. But, most purchases aren't via Amazon or other low volume sources, as typical purchases run in size from a handful thousand units to millions.
To be warehoused, then auctioned off at the end of the fiscal year, so that they can reorder new units. Gotta justify that budget!