Think about it. This town can't have been the only place the toys got shipped too. What happened everywhere else!?
Answered in movie, Original-Chip got reinforcement from the mall the rest were shipped to, the implication being that only Original-Chip was activated early. The Rest were probably recalled.
It's actually a good thing the original toys got found out on this small scale before they were shipped out - especially if they can bust out of their own cases.
The climax of the movie involves an electromagnetic pulse that we see cover the entire neighborhood. In a previous scene, we see an elderly couple turn the volume up on their TV to drown out all the noise outside. What if one of them had a pacemaker or other electronic device as a necessity?
"The X-1000 is a masterpiece. Imagine a microchip sophisticated enough to control the guiding systems of ballistic missiles. Imagine it can be used to instantly upgrade any system that its plug into like a smart drug for machines. Then imagine it can learn." The MacGuffin of the story that enables the AI of the toys. It is a control chip for ballistic missiles. Now, imagine there are sentient ballistic nuclear missiles out there. Let's hope sentience also gives them the need for self-preservation. Hell - just imagine what the chip could do implanted in to any electrical device around you.