Vantaggi
The company really does promote from within to a point. If you have any college education, and are good with people, you can go far.
Svantaggi
They will never directly admit it, but you can not get past a supervising roll without a college degree. You can essentially run a department for years, but when they officially fill the management role, they will hire outside the company for someone with any degree instead of the person who has the work experience. Without a diploma you will never get a salaried management position in this company. An associates degree in art history will get you further than 20 years experience in customer service.