I think, its a good idea to study cultural effects but then, you need to think what kind of culture you want to compare in the industry. I am referring to things like national culture, organisational culture and so on. You also need to consider how much time you have to do your dissertation. Is it 3 months or more than that?
Narrow down yr topic, employee commitment will have a whole body of literature of its own….may be you need to think of that?
How many bodies of literature, can you study, in the time you have?
Right now, you seem to be thinking of quite a few bodies of literature:
national culture, organisational culture, employee commitment,customer service,operations management (u have talked about night shifts). Each of these can be a dissertation topic. You need to choose one, or at the most, two; depending on your time limit.
Let me know if this helps.