I have just returned from Budapest and was amazed to see that a lot of the scaffolding used there is made of wood and not metal . The construction itself is wonderful and almost an artwork but I cannot see any advantage in using the wood which will rot in time.
Countries such as Budapest usualy don't have the industrial capibility of other countries that do use metal scaffolding.
The wood scaffold you talk about is not a working platform. It is put in place to protect people below from falling stonework on old buildings which are waiting for repair. I am sure that when the work can be done it will be replaced by a metal scaffold. As it may be a while before the work can be afforded the wood structure is cheaper to leave in place to keep the public safe.
Wood is cheaper in most cases.