Knitting is kind of like this as well. No one really saves money by knitting a hat themselves. It's fun and you get something in the end that you made. Preserving and canning is more economical if you have a big garden and use it as way of extending your harvest. People used to have to do it to have something to eat in the winter. Your description of jam making makes me want to try.
Free food is not proper compensation for working long hours. The Department of Labor has guidelines about which positions need to be compensated with overtime and which do not. You should make sure that your company is operating within those guidelines.
@Emma Peel This is exactly what I was thinking. $38,000 is nothing compared to what some people borrow to complete a professional or advanced degree. Count yourself lucky.