He permitted Travis to rob a store but he said to leave cash. I don't think Will actually went himself.
"That should do it,' he said. 'But we're going to need some mortal supplies.' He grabbed a piece of hotel stationery, jotted down some notes, and handed it to one of the Athena guys. 'There's a Duane Reade on Fifth. Normally I would never steal—'
'I would,' Travis volunteered.
Will glared at him. 'Leave cash or drachmas to pay, whatever you've got, but this is an emergency. I've got a feeling we're going to have a lot more people to treat.' Nobody disagreed. There was hardly a single demigod who hadn't already been wounded . . . except me. 'Come on, guys,' Travis Stoll said. 'Let's give Annabeth some space. We've got a drugstore to raid . . . I mean, visit.'"