I've seen it happen in Consulting/Defense Contracting it's pretty common to have well paid PHD's around as subject matter experts for certain topics. Not to mention having PHD resumes on proposals can mean a lot to prospective clients, so even than can be worth it for that industries to have well educated peeps on the payroll. Overall, in the DC area at least (what I know), having a PHD can pay. Hard sciences, engineering, even social sciences. They have to usually be socially competent too, not all PHDs' possess this trait...