There are two options for building hotels near cultural sites around the world. One is to build them far enough away so as to not affect the site--tourists can be transported into the area. The second option is to build facilities in line with the area's culture. For instance, a hotel built near the Mayan pyramids can be made of the same type of stone used to construct the megaliths. Transporting or blending are two easy ways to satisfy travelers while maintaining the sanctity of the cultural site.
Yes, cultural conservation can be maintained even as tourism develops, because culture and the unique, special things about a location are often the reasons tourists go to a specific destination. If a location becomes too much like other places, people may not want to visit there. Local governments and even local economic unions can put rules in place to make sure that culture is maintained as tourism grows.