A term is associated with this specific group of people. While this is a general term it has an Ann Arbor connection. What?
My sincere apologies for the parochial nature of the question. Extra credit if you crack this w/o the Ann Arbor hint.
Answer: Gandy Dancers. Arising from the way people look while working on the railroad. The Ann Arbor restaurant that is located in the old train station takes its name from this term.
Answered by: Raghu, Rajeev, Manix, Jaggi, K, Anand and Karthik. Extra credit to Anand who I know has no AA connection.