I think like most "weird Japan" articles this one is being mischaracterised somewhat.
It is often somewhat difficult in Japan to get your legal entitlement when leaving a so called "black" company. They might not easily pay out your remaining holiday, or they might use "power harassment" to otherwise make your exit process difficult.
So I can see that a company like this, while not providing legal services, removes the possibility of applying harassment to coerce employees to stay a bit longer or not take their full legal entitlement.
I mean, there's also the fact that these stories never tell you how prevalent or not these services are. All the attention showered on these unusual services can give you the idea that every second person in Japan is using them when that's far from true.
No, but this service did also do the rounds in Japan. In this case it's most likely not very useful, but I think people can understand what the utility might be (and the social context in Japan in a little different).
Don't know, but I would guess that in most cases they want to coerce people into giving up their rights. I.e. "sign this to agree you give up your right to X". That might be remaining holiday pay or something else.
Actually... thinking back I've literally had an ex-boss in Japan try to get me to sign releases to various things. In the end I paid a lawyer to tell the guy to stop harassing me. This service would have been cheaper...
It is often somewhat difficult in Japan to get your legal entitlement when leaving a so called "black" company. They might not easily pay out your remaining holiday, or they might use "power harassment" to otherwise make your exit process difficult.
So I can see that a company like this, while not providing legal services, removes the possibility of applying harassment to coerce employees to stay a bit longer or not take their full legal entitlement.