One of the reasons bed bugs are spreading is that they used to have an insecticide in mattresses. They removed it several years ago because someone decided it was a carcinogen. Looking at where you buy is not a good indicator of bed bugs. My sisters in laws got bed bugs from a really fancy bed and breakfast. One of the fanciest hotels in New York city is infested with them. You need to inspect everything and check for signs.
The whole thing totally grosses me out.