What a brilliant question.
I know that in Lille, statues such as 'les fusilles' were pulled down by the occupying Germans - not heard anything about the cemeteries though.
Glad to be of service.
I believe it's an unwritten rule among soldiers of any nation that war graves/cemeteries would never be dessecrated at will.
Combatants in conflicts tend to respect other buried combatants.
i was lucky enough to go to oak Dump Cemetury in Belgium 2 yrs ago to visit my Grandads grave from 1917. We also stood at Menin gate and it was so very very touching! Everything was so emmaculately kept and looked after well .