This is similar to how I talked my brother out of his brief thoughts of becoming a professional pilot. It sounds wonderful, but in reality the pay is poor (unless you're one of the lucky few able to work their way up to a good long-haul route), a lot of it is boring, a single relatively harmless medical problem can end your career, etc. etc.

You have to look at the bad parts of any job when considering a career or starting a business, and it seems to be something that people are bad at doing.