The biggest difference between a common man (as you call it) and an investor is that one of them is fully dedicated to making his/her money produce more money. It's not a hobby or a side income, it's their main drive, they invest the time to research the avenues and opportunities, they develop a mindset and discipline that shapes their way of life and way of thinking. They can see a product or a business and not think about it from the consumer's point of view, bur from the entrepreneur and try to figure out how it was achieved under what market conditions and what, the presence of said product or business, means for the industry in order to assess the financial advantages or threats. Since they understand the market fluctuations in a deeper manner, they're purchase habits and payment method can differ greatly from the common man as well.