Graeber makes no distinction between "useful" as in: a) creator of exchange value to it's maker; b) creator of utility to it's holder; b) psychologically "meaningful" to the worker. And while the core of the article deals with the latter, by not making this distinction he dangerously suggests the two former.
As much I'd like to believe that managers are stupid, they're not crazy to hand out free money. If an employee generated no additional income to it's employer, there would be no reason to hire him in the first place. Similarly, if the holder of a good derived no enjoyment from it, it would be of no value at all to him.
It's hard to believe, for instance, that a "corporate lawyer's" work has no social value. The job of lawyers isn't even to win legal battles, but to avoid them in the first place. The job of a corporate lawyer is to ensure corporations are compliant with all the paperwork necessary to their operation. For sufficiently large corporations, they're a necessary condition for it's functioning.
For me, the only reason why his argument might seem personally intuitive is because the majority of things in capitalism are of no use at all to any given particular person, even if all of them are "useful" in some way. Paparazzi, dog-washers and all-night pizza deliverymen are useless for all but the people who demand their services. It's not hard to see why consumers would have little interest in contract law if they deal so little with it, and when they do, their job of understanding it has already been cushioned by a specialist.
I see little point in coffee shops. Nonetheless, people flock to places with well-developed service economies that offer such things (e.g. New York, San Francisco) along with dog-washers. Perhaps because they know they'll cater to their bullshit tastes too.