@darius both American "cheese" and the stuff in jars and squeeze tubes typically come off the same production line and have similar ingredients. In fact the sauces and squeeze cheese often consist at least partially of off-spec/rejected american cheese slices.
Also Americn cheese is partially made from rejected/reworked cheddar.
so...Velveeta is the rejects of the rejects of cheddar...
A lot of (maybe most?) processed/snack food was invented as a way to reduce scrap.