Surely your goal as an antrepreneur shoul dbe to provide a million people with a desirable new product/service/ The word 'entrepreneur' means 'between-taker', ie someone that carries things back and forth between suppliers and consumers, like historical traders.
Identifying economic inefficiency and finding something to remedy it is one way of identifying your target consumer, but far from the only one. In your example of the shipping container, you neglect to consider that they're only useful insofar as there is sufficient trading activity taking place to fill the containers up. Labor shortages aren't often a big limiting factor on trade.
I think it would be great for society if there were less jobs and people were able to pursue more creative endeavors than menial jobs.
So do I, but creativity and productivity are wholly different things, especially when it comes to paying the bills.