Yes, they are. The 'Hostel' films are loosely based on real stories of backpackers disappearing in certain parts of Europe. However, they are highly fictionalized for the horror genre, with lots of added gore and extreme situations that may not be exactly as in the real incidents.
Often, they tend to have a sense of realism. For example, in 'Hostel', the seedy and sometimes dangerous nature of some hostel environments is portrayed realistically. They might also show the cultural mix that occurs in hostels. In true - story - based hostel films, there could be real - life events that drive the plot, like a mystery or a discovery that happened in an actual hostel.
Yes, some hostel films are based on real stories. For example, they might draw inspiration from real - life events of travelers' experiences in hostels, like the unique encounters, cultural clashes, or strange happenings that can occur in such shared accommodation settings.