Well, if I can 'pay' the employee a lot more just by letting live somewhere cheaper where he'll happy ( say, somewhere with a house, garden, and peace and quiet, an unaffordable luxury to most in large European cities such as London/Paris ), then wfh and compensation suddenly become linked.
Furthermore, by allowing full WFH, you also expand your recruitment pool to people outside your immediate geographical area.
That being said, I miss the office quite badly : real, physical interactions, can't be replaced with video conferences.