So that's why they were at the sporting-goods store.
E! News has learned exclusively that the Jonas Brothers helped celebrate Nick's sweet 16 birthday last night at Los Angeles' Dodger Stadium.
"[Kevin, Joe and Nick] rented out the stadium last night to play a baseball game with some friends," a source tells us.
The famous trio joined at least 15 of their closest pals (the minimum required for a baseball game) from 10:00 p.m. to around 12:30 a.m.
Just how much did the guys drop on baby Nick's sweet 16 treat? Upward of $30,000 for the less than three-hour affair.
Just renting the field starts at $25,000. From there, lights for a night game run $5,000, and food and beverages can add up to $500. Want music? Bring your iPod to blast through the stadium for another $500. Staff, amenities and even hired baseball players can be added to the package.
The Brothers, however, preferred to bring their own uniforms. Earlier today, E! reported the band scooped up baseball gear from Big 5 Sporting Goods, including athletic pants and shirts.
A rep for the Dodgers had no comment. The Jonas Camp has yet to return calls.