I don’t why operating such a business in a train station is any different than anyplace else. One still must run the numbers and compare lease costs per sq/ft, lease terms dictated calendar and hours of operation, utilities, inventory storage, state/township permits and licenses (more complicated and expensive if you prepare food on premises), insurance, security, etc. and compare all that to estimated sales revenue.
Like any business, long-term experience in the field is probably the most valuable, if elusive, asset one may need.