My personal strategy is to heavily play with the displayed stuff in a randomized fashion...
...and washing my hands afterwards...
seriously: I own almost a copy of jochens display case and use collector cards acryl boxes for extraordinary figures and customs.
my playmo ships I have for display in the double faced windows in my appartment are doomed for dust...
...as long as my son isnt asking for them.
(...but never forget to wash you hands afterwards.
)
best,
socrates