A PhD in economics will help you work as an economist. It will not help you run a business.
I will tell you right now that $7/hr will not even pay your rent.
Masters in economics, LOL!
Well lets see....7 an hour at 12 hrs a day 7 days a week 4 weeks a month and 12 months a year nets around 700k assuming full capacity. Even if profits are 25% of this, implying that we are at full capacity for a mere 25% of the year,it would cover the costs. This does not include revenue generated from food sales and membership options, and social events. Maybe you need a reality check.