Research stations often performed scientific research that was too dangerous to conduct in populated areas. Some stations, like the Regula I Space Laboratory, also conducted highly classified research. (Star Trek II: The Wrath of Khan)
One example of a surface research station was the Federation research station on the planet of Ventax II, some of whose personnel was taken hostage as the facility was overrun during a riot in a period of civil unrest on the planet in 2367. Given that this station was located in an inhabited area, its area of research was unlikely to be dangerous. (TNG: "Devil's Due").