Bed Bugs!
This shabby, over-priced hotel served only doughnuts for breakfast. It was the last hotel of approximately 25 hotels I stayed at in a huge loop driving trip of the USA. Although all the hotels cost less than this one, this is the one that had BED BUGS. 
I was bitten over a hundred times on the arms. Big red welts that itched terribly for 3 days. The management denied the problem and is doing nothing to remedy it. They said, "We have had many false reports of bed bugs."