The monster's so destructive that if left be, they'll create an even bigger destruction or leave the area with nothing intact... at least if Kanji and his True Companions move their asses to save the city, while some will be ruined, some isn't everything.
Zig Zagged: The village is untouched by the battle, but then Pike sneezes and half the town collapses. However, it was intentional because that part was cursed by the monsters the heroes just defeated. The villagers are still upset, until Kanjii announces they'll help rebuild. They cause more actidents, but ultimately rebuild what they destroyed.
Averted: Kanji and their friends always attempt to engage with their foes in an area where the damage from their fight would be minimal; and are always extra-careful if the battle occurs in a populated area.
Lampshaded: "Thanks a lot Kanji! The 10 pieces of gold you managed to recover from those thieves almost justify the destruction of our beloved town".
Exploited: As soon as they find out that Kanji is comin, the villagers prepare to commit massive insurance fraud.
Defied: The heroes are accompanied by Popoi, a Fairy Companion who specializes in casting protective barriers that keep them from wreaking too much havoc during their battles.
Discussed: "We might be the monsters, but all we did was set a house on fire. To find us, they set the whole forest on fire".
Conversed: "The heroes made more of a mess than the villain!"
Deconstructed: Because of all the destruction they cause, Kanji and his friends aren't viewed as wandering heroes, but villains. A bounty is put on their heads, and they have to deal with eager hunters along with all the other threats already facing them on their journey.
Reconstructed: The kind of enemies that Kanji and their friends are fighting happen to be the kind of beings that cause an incredible amount of destruction by just waking. They know the casualties are unavoidable as long as they keep fighting them, but it would just get worse if they don't.
Played For Laughs: Kanji's reputation precedes him, and people desperately attempt to deny their help. Unfortunately for them, Kanji is a well-meaning Idiot Hero, while Ichigo Jumped at the Call, Pike's just out to have fun fighting monsters and Yumi's the Only Sane Man trying to rein in their destruction while pointing them towards Emperor Evulz.
Played For Drama:Kid Heroes Kanji and Ichigo barely have any control over their powers, and this results in them unintentionally wrecking havoc while fighting. This often causes the very people they're trying to protect to turn on them. Pike and Yumi are the only people willing to stick with them; Pike tries to convince them not to worry about it, insisting that the important thing is that they mean well, while Yumi is trying to make them reel it in... and is aware of a prophecy that her companions don't know of yet. A prophecy that states two Chosen Ones will either save the world... or destroy it.
What?! Aaargh! You broke it again! Go back to Destructive Saviour! I don't want to see your troublesome face around here.