Never heard of the p2p reputation at Yale. May be true, but have never seen it. My understanding is that it would only help if the kids weren't going to get in on their own merits, and by all accounts, this was not an issue. It is a signalling mechanism that they are going to pay full price or more, but I see no evidence that they bought their way in.
Kushner offered a lot more than a million a year, and had a politically connected father and it was a generation ago.