@danicaswanson
To add to what @y0b wrote above...
Gift culture definitely relies on social norms (I also like the framing of "weaving a web of gifts"), but it gets complicated quickly since social norms are influenced by structural factors. Without sufficient systemic support, social norms can only go so far.
I'll quote-cast your questions into the channel and add some more thoughts, Chris.
I'm not familiar with the Founders' Pledge, but it sounds like maybe a type of philanthropy?