Is there a word for this: when the tradition is maintained in form but not in function?
skeuomorphic - Pertaining to skeuomorphs, obsolete design elements which are retained for familiarity or out of tradition, even though they no longer serve any functional purpose.
There was this funny study that found that people were more likely to hold their hand next to their nose right after shaking hands. From this they concluded that hand-shaking is a non-intrusive way of smelling a person you just met.