I think the real question should be, "What can't you do with a theatre degree?"
The answer is very little. My theatre training has prepared me for every challenge I have even undertaken. Business is reading people and situations. Meisner. Any team would benefit from a stage manager to keep them on target. Project Management. Any team would benefit from the creative perspective of someone familiar with good timing, in a space, under the pressure of high stakes deadlines with no budget. Event Management. HR is helping people find a neutral space and pursue objectives. Wardrobe is personal optics. It never ends. So many career parallels, if we just take the time to find them.
You could look at business end roles within the theatre. Every production needs an executive producer, marketing team, house manager, stage manager, director, and so on. You could also, as Keenan said, teach theatre in the school system.
Possible career paths for a Theatre/Acting major are several in approach, my role was that of a “Feature” meaning I was showcased with or without lines. In the network television Drama ‘Smash’ I was in the ensemble of the musical being created that was the focus of NYC theatre. But once I received the ‘feature’ status, room for growth became very possible. I was always in contact with directors and ’stars’ on the set was always asked back for other episodes as the result of my hard work. For a hopeful actor this is advantageous because it can easily lead to a ’Screen test.” My work with NBC led me to Cinemax, and Warner Bros productions before returning to Chicago to finish my undergraduate degree.