A new lease on death

While reading the local news the other day I came across an article complaining the cost of 20 year and 30 year leases on graves in the Netherlands had gone up.  After further research I learned that most grave sites here are leased and then dug up after the lease expires (provided the next of kin do not want to extend the lease) and the remains are moved to a mass grave. 

It makes sense (lots of people, little land) but not something I had ever thought about.