They probably are included.
All I was trying to do was point out how an average base salary in the $30k range can easily add up to a total cost upwards of $500,000 for 10 people. It costs a lot more to employ someone than most people realize. This is another reason why we have to be careful about those demands to raise salaries to a "living wage" because of all the extra expenses that get added on. Some of those extra expenses (like SS and probably unemployment insurance) go up proportionally with the base salary increase.