There has been a great deal of talk in the biology literature of the
fallacy of the "adaptationist" assumption that if we observe something in
Nature (e.g. honey bee workers drifting between colonies) there must be
some way in which it serves the evolutionary interests of the organisms
involved.  Well, it just ain't necessarily so.  In this case, one could
argue that in Nature before Apiculture, honey bee colonies were quite
dispersed.  Under these conditions, the chance of a forager encountering
another colony would be relatively remote.  So there would be no selective
pressure for bees to evolve adaptations to prevent them accepting another
colony as home.  When we cram them together in an apiary, they sometimes
are not sufficiently oriented to precise location of their own hive that
they wander into others.  I think its remarkable that it doesn't happen more!