In N Out has been in business since 1948, first one opened in Baldwin Park. The menu has not changed in 63 years. Their service and quality is unmatched. They also start their employees at a minimum of $10 an hour plus benefits...try getting that being a Whopper flopper at Burger King. They keep their employees happy, and that translates to an excellent customer experience. All of their food is fresh, no preservatives, and is bought locally. They give a lot back to the community. It is NOT a franchise, it has been owned and operated by the Snyder family since day one. When it comes to "fast food" there is NO comparison.
You can read more on the history here:
http://www.in-n-out.com/history.asp
The prices are not bad either, take a look: