In Hawaii hospitals give it to patients routinely, if you don't want it you have to tell them.
It's interesting that your FIL's wife's culture has a lying in period of 40 days because in Islam too a woman's babymoon is 40 days.
In my DH's culture they don't leave the house for 40 days but that's bit extreme for me - I'd go stir crazy.

I came across the traditional Chinese method for drying it while I was googling placenta eating.