These laws are necessary because it's self-evident that elites controlling the status quo can't police themselves.
At face value, entitlement was never burdened by the concept of shame.
I don't think the stereotype that the "rich kid" who got in was a C student who's absent parents just paid the right people is accurate. A lot of these wealthy students are more than qualified, the schools themselves don't have enough seats. On paper, they are mostly identical students, credentials-wise, and the legacy got in because Dad donated last semester.
The z-list is very small (on the order of tens of students per year) but matches the stereotype.
The typical non-zlist legacy student is qualified to attend and has test scores well above the admission median. I am not sure they even consider past donation history for these admissions. A more important factor is that they feel that legacies are more likely to attend vs go elsewhere (the 'yield rate'), which lets them lower their admission percentages further.
In some ways it applies to rest of the community as well not just rich people. For example the whole school district thing in US; where you get to go to a better public school if you can afford to live in better neighborhood.