In "Kootie Pie Rocks", the boy band Milli Vanilli insisted they couldn't sing for Kootie Pie without their backup band when she kidnapped them and tried to force them to perform. It may have been unintentional on the writers' part, but the fact that their real-world counterparts were outed as lip-synchers mere weeks after the episode's initial airing sheds some light on their claim.
In "Crimes R Us" Cheatsy steals a kid's lunch money to get him to help them capture the Marios and then uncharacteristically gives him his money back after he's done his job instead of just keeping it anyway. According to the series bible, Cheatsy forges counterfeit coins in his spare time, so he could have switched them with fakes.
Fridge Horror
Think of the episode "Oh Brother". If Luigi hadn't saved Mario, he would have been kept by the Koopas and they could have ended up using him to do their deeds while being completely aware of doing so. Note that the argument and Mario's capture was all Luigi's fault. That meant Luigi would have caused the downfall of the Mushroom Kingdom.
"Crimes R Us": Crimewave Clyde is, according to the Koopas, Public Enemy #1 in the Real World and had been serving a 12,000-year prison sentence for undisclosed crimes. It's anyone's guess as to what he was in jail for and why the Koopas would bust someone as dangerous as him out.
While the Koopa Kids are robbing the Mushroom citizens, Big Mouth pulls a Ptooie on Kootie Pie and forces her to hand over her loot. Suppose he didn't just simply take it from her if she refused...
"7 Continents for 7 Koopas": Some of what Mario and Luigi do to chase Koopas away counts. Mario turns the Great Wall of China into a dragon and floods the Louvre, potentially destroying it while Luigi makes the penguins gigantic in Antarctica. Were Asia, Antarctica and Europe better off without the help of the Mario Bros.?
It's possible the Mario Brothers used the wands to turn everything back to normal after the Koopas were defeated.
