Economical if they have money to burn--or no choice.
Macs cost less in the long run: they last longer (so you buy fewer), stay fast and stable longer, have lower support costs, and great resale value. These are concrete, measurable facts, and they save you big bucks.
Add up the TCO of Macs and Windows PCs, and you'll find you can get nicely-spec'd Macs for cheaper than low-end PCs that will bog down next year.
And if you compare ALL specs without cherry-picking, Macs haven't been more expensive than PCs for years. Sometimes they're much cheaper, sometimes a little more, but generally right in the same ballpark as other name-brand PCs of similar specs. Apple simply has no low-end "throwaway" machines in the lineup, making the average price higher. (The iPad is a great PC in that low-end price category--but a different kind of PC obviously. Suitable for many people, all the same!)
I've recommended those throwaway PCs (low-end Dells) to friends who had no choice: out of work, need something to send resumes from, whatever the case may be. I regret it. They got what they paid for