Army Men/WMG

The Army Men series takes place during Life After People

 * At least in the early days of post humanity. Pets are still alive, power sources are still running, and insects are still in the process of taking over houses. Heck, it's even possible that the event that took away humans is what opened the portals between the worlds.
 * Jossed for the Sarge's Heroes series at least; Plastro and Bridgette get to a toy store by stowing away in a kid's backpack.