The anniversary event is what determines whether a person is a good or bad member of society.
To put up an anniversary offering is an easy, convenient task and one which we all recognize as the correct, appropriate thing to do. To put up an anniversary offering is objectively right. There are no situations in which a person is not able to put up an anniversary offering. Simultaneously, it is not illegal to put up another offering. Therefore the anniversary event presents itself as the apex example of whether a person will do what is right without being forced to do it. No one can stop you from not putting up an anniversary offering, no one will be able to go after you after the match is over if you don't bring an anniversary offering, you can get a ton of bp just from the offerings other people bring. You must put up an anniversary offering out of the goodness of your own heart. You must put up an anniversary offering because it is the right thing to do. Because it is correct.
A person who is unable to do this is no better than a sable main, an absolute savage who can only be made to do what is right by bribing them with sex rp and revealing skins