The ending of the "Box Top Bandits" story arc confuses me. Wasn't scattering the box tops around exactly Boris and Natasha's plan anyway? If scattering their box tops around the country would crash the US economy, won't their spread through the city wreck its economy even worse given the concentration? Sure, B&N didn't succeed outright, but it's hardly a happy ending.
The lion's share of the box tops were found in the elevator shaft earlier on and destroyed, so the box tops distributed by the explosion aren't enough to significantly distort the market any more than it already was, and with the press gone, Boris and Natasha couldn't make any more (What stopped them from getting a new press and starting over since they were never caught isn't brought up).
This could also be a case of Screwed By The Sponsor. General Mills didn't appreciate the story arc that much as they thought it cast a questionable light on cereal companies so the arc was ended abruptly. (Bullwinkle testifying that he eats a lot of cereal should have certainly cast them in a brighter light.)