This^^
I was thinking opportunity costs, margin and utility the whole thread. It really is more complicated than just dollars and cents.
I had a similar conversation with my brother-in-law about "the cost of my time". We were actually talking about me finishing my basement, but the concept still applies. His argument was that I had to factor in X dollars an hour that I spent working on the basement. I agree there is an "economic" value to my time, but that doesn't always translate to a dollar value. I saved a ton of money by doing the work myself and argued that nobody was going to give me money for an activity (unless I took on a second job) that I did instead of finishing my basement. Sure, there is opportunity cost of not doing something else like sitting on my butt or playing golf... but that missed opportunity would not translate into more money in my wallet. I don't agree with saying "you have to figure in the cost of your time" into the dollars and cents calculation of the cost of home brewing unless you are going to spend those 5 hours doing an activity that actually pays you money. If you take off 5 hours of work (hourly employee) to brew beer... then you should factor it in. My guess is that most of us would spend those 5 hours doing something else besides working extra hours in our hourly jobs.