(source: I know several.)
There is certainly great value in humanities, but that value shouldn't be determined by "an unrelated field is hot, so let's make hot money too".
Especially when it's other people footing the bill, and especially with what's going on in humanity departments these days.
Rent in a major city is $2000/mo. Student loan payments can be in the tens of thousands per year. Assuming a normal tax rate, professors would need to make 6+ figures to live comfortably.
That's not necessarily a bad thing.