MBA in retail is common. Actually MBAs themselves are more common than other graduate degrees so having one can be an expectation for entry level jobs. In my current career field, certifications tend to be more valuable than a graduate degree (i.e. PMP, CSM, DataPower Cert, etc) .
A MBA is a waste at the Sr.TL level or below. Good if you intend to move up the retail chain (ETL, STL, DTL, GVP, Corporate). If you're willing to relocate to MN they hire MBAs. However with upcoming cuts I'm not sure it will be happening.
To be clear, a degree isnt required to run a store. I think experience is the best for that. But if you have a MBA I'd suggest looking around. Lowes and Home Depot have good options - especially at distribution centers. My friend moved from Target to Home Depot Online Distribution Center and works M-F doing exactly what he did as an ETL-Replenishment. Also Carmax is run by ex target executives.