As the online shopping window is closing for traditional home delivery, PetSmart is offering free same-day shipments until Dec. 24. The service is available in 17 metro areas across the nation, including Boston, Los Angeles, Orange County, San Francisco, San Jose, Las Vegas, Atlanta, Miami, Seattle, Chicago, Dallas, Houston, Philadelphia, Washington, D.C., New York City, Yonkers and Northern New Jersey. Overall, the same-day deliveries will cover nearly 2,500 ZIP codes.