Carl Steiner walked to the window of a small gray building near downtown Phoenix and gave a worker his name. He stepped away with a box and a cellphone bill.
The box is what Steiner had come for: It contained black and red Reebok sneakers to use in his new warehouse job.
Steiner doesn’t have a permanent address. His letters and packages are delivered to a mail room for homeless people in the building at the Keys to Change campus, a collaborative of 15 nonprofit organizations that serve those like him…