I don't see anything wrong with this if the parents want to share credit with their kids. In any case, there are many cases where authorship is shared with people who didn't contribute, if universities are taking it at face value that's on them. Also, who is to say that the kids weren't onvolved in some way, maybe just as a person to bounce ideas off of.
Nepotism is majorly harmful. If their kids go into academia, they already have a huge leg up from having academic parents. Let alone if they already have a strong publishing record which they did not merit. You really harm those who don’t come from that background, which of course, is how class divide can become a chasm.
I think it is the norm that a lot of people get primary credit on papers for doing what managers in every field do every day, and academia is busy obscuring their own processes as a result.
One fraud doesn't justify the other.
Hollywood has a credit format.. programmers have a change by change attribution system.
A serious limit to academic reform is that an institution that fixes its own rules will have trouble competing for people in many positions by having to be completely honest about the roles.
This is the sort of thing that's only a problem when your own prerogatives are misguided. Must academe be merely another institution that must pursue growth at all costs? If so then is the pedestal it presumes to occupy legitimate?
To put it differently, poor ethics is possibly a necessity to outcompete other institutions in what should be a net zero game. Instead the game is negative, we view academia overall as worse than n years ago because of the progressively lower ethics, higher administration costs and staff to compete for the same grants, etc.
Given the reality of living in a world where references lead to enrichment, this should be considered fraud in every case. The authorship system hinges on trust. Abusing that trust for family gain is wrong.