You probably don't spend 8-10 hours per day eating/preparing food, nor driving, nor running etc. You may engage in those things, but you're not an expert in those domains.

The OP point was that there's many lucrative domains out there that don't have optimal solutions to their problems yet, but most people who do software all day only really understand the ins and outs of the software dev industry as opposed to, say, the funeral business and their unique needs. Yes, you probably have been to funerals, and even said "wow, i've got a need/want for better funerals", but really digging deep in to an industry takes a lot of time and effort.