okay, Lois not knowing Bruce's secret identity is WRONG. Hell a later Superman/Batman story had Lois nearly figuring out their identities in a flashback, with only Clark's superpowers hiding them. Once she knew about Clark's powers it'd be easy to figure out the ruse.
I think the Kents at least knew about Bruce and Dick. Or at least Ma did. One of the stories in Justice League of America 0 had the Trinity in the Kent's kitchen after Jonathan's death. It was just a possible thing but I have a feeling Batman and Robin would find some Superman related reason to be at the Kent farm and be comfortable enough to let them know.