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They are trying to get the online companies to do it because most citizens DON'T report their online purchases when doing taxes. The online companies say that it is far too confusing as various cities and counties within a given state charge different sales tax rates.

I don't believe sales tax applies at a garage sale...

Exactly, and no, sales tax doesn't apply at garage sales.
 
Ont thing you have to keep in mind is if you buy from MacMall, and you have an out of box failure or defective machine, you have to deal with MacMall not Apple. An Apple Store will fix it under warranty, but will NOT swap you for a new machine, even if within the 14 day window. Apple will direct you back to the seller for exchanges.
I learned that lesson I never will buy a mac anywhere but Apple.
 
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