With the peak shopping season approaching, Urban Outfitters (URBN) is asking its employees to pitch in a bit more on the weekends. But there's a catch: they won't get paid for it.

In an email obtained by Gawker this week, the Philadelphia-based retailer told salaried employees that it was looking for weekend volunteers to help "pick, pack and prepare packages" for wholesale and direct customers.

Urban Outfitters, which operates its namesake brand along with Anthropologie and Free People said it would be a great "team building activity." Employees can sign up throughout the five weekends during the busy month of October. The company will offer transportation and lunch to those willing to show a little team spirit.

Urban Outfitters told CNBC it "received a tremendous response" from employees.

"Many hourly employees also offered to pitch in — an offer which we appreciated, but declined in order to ensure full compliance with all applicable labor laws and regulations," a company spokesperson said in an emailed statement.

Earlier this week, New York Attorney General Eric Schneiderman said Urban Outfitters agreed to phase out and eventually end on-call shifts in the state starting in November.

As a part of that agreement, Urban Outfitters also agreed to "provide employees with their schedules at least one week prior to the start of the workweek, said in a statement. "Workers deserve basic protections, including a reliable work schedule that allows them to budget living expenses, arrange for childcare needs, and plan their days."

The company joins retailers Abercrombie & Fitch (ANF), Gap (GPS) and L Brands (LB)' Victoria's Secret and Bath & Body Works in agreeing to end on-call shifts, which require workers to be available for shifts that may be canceled with little notice, according to Reuters.

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