Or because a flood was coming?

Not sure what you mean by like the Gideon's bible. Are you asking if they were placed there for future travelers to come and read when they stayed in caves? If so, the answer is probably no. The caves seem to have functioned primarily as caches, not somewhere people lived. Plus, most of society wasn't literate (and writing stuff was difficult without printing), so there wouldn't be much reason to do such a thing.

There are some questions about exactly what the community that created the DSS was like. But the scrolls seem to have been a document repository of some kind for both biblical and their own sectarian texts, not reading material for passers-by.