Bro, they live in the boonies and there is a bear sighting. The 2 species of bears in Japan are both known to be dangerous.
Also, what are you gonna do when you get a suspicious person report and the moment you get there, you see that suspicious person terrorizing children?
I hope you're being facetious and it's going over my head.
I am being facetious and serious both, and since you seem to be engaging in good faith I'll elaborate. You've raised two arguments.
First, the bear. "We've heard there's a bear so we're pulling kids off the mountain" is an overreaction. Yes, bears are dangerous. So are cars, gas heaters, mosquitos, and running with scissors. People who live in bear territory typically know what to do when they encounter a bear. It's not the police's responsibility to drive around and force people to avoid risk. Let's also objectively describe what the cop actually accomplished. They never encountered a bear, they were never in danger. But they did stop him from getting some tasty fiddlehead ferns (Can confirm, they're a treat!).
Second, a "suspicious person terrorizing children." There's a lot of qualifiers and subjectivity in that statement. What are we judging is suspicious, how are they terrorizing the children, etc. If they're just asking for directions or giving the kids their ball back, then involving the police is an overreaction. But let's assume it's the worst case scenario and the kids are in danger. You can call the police, then wait for them to arrive. Unlike on TV the cops don't rush at the speed of light and arrive in time. They could take fifteen minutes, they could take an hour. By then the harm is already committed. Instead of assuming the police will swoop in, I would approach the suspicious person and redirect them.
What actually happened? In this story, the police officer IMMEDIATELY resorted to violence. He didn't take stock of the situation. The costumed mascots were not touching inappropriately, screaming at, or restraining the kids. They were just near the kids. The officer COULD have walked up and said "What are you doing with this costume around these kids" and found out that they were official city mascots. Instead, he tackled one and hurt them. One of the mascots was crying after being attacked. Objectively, the police caused far more harm than the suspicious person. And speaking of "Terrorizing children," the cop caused some discomfort and terror to our main characters by escorting them off the mountain, glaring at them, and asking them about their romantic lives (They're children! Maybe not appropriate to ask children about romance.)
I know that these are fictional police and their behavior was exaggerated for comedy, so in that sense my "ACAB" joke is a little facetious. I do think that studies of policing in real life don't paint the police favorably, and that there are better ways we could encourage neighborly behavior in society. The arguments for "ACAB" would extend this post quite a lot, but if you're interested I'd continue. For now I'll make some generalized claims that form the basis of why I'm happy to say ACAB in a gag manga.
1) Police don't prevent crime, they punish people after crimes have happened. This
may deter crimes from happening, but there are other less violent ways of deterring crimes.
2) Crimes and Laws are not absolute rules. Often they are written to defend the power and authority of the dominant socio-economic class and to harm the oppressed classes. This is especially true in my country, the USA, which has the highest population of prisoners per capita than any other country. Most of them are people of color, poor, and non-violent offenders.
3) Media representations of police wildly misrepresent what police actually do in practice. This "copaganda" creates a false image of professional and competent police, when the reality is that many police are thugs. I'll link to this detailed study of
criminal gangs formed within the Los Angeles Police Department. Copaganda is a powerful tool that oppressive states use to manufacture consent for state violence, and it should be called out and challenged, even in fluffy romance manga or children's cartoons. After all, it opened up this dialogue!