I think⚡zaps are just another implication of hard deflationary money vs inflationary fiat.

Specifically the wealth effect. When you have hard money and it grows in value, you feel wealthier and are more likely to spend it. When it's inflationary easy money, you get increasingly poorer, so you try hold on to whatever you feel you have left (the opposite of the common lie that deflation makes people hoard so they can spend later). That makes money, like zaps, flow easier.

And you get the effect from the receiving end, where you know that you're receiving something of real value that will last, which motivates you to do something with it or to pass it on as a good deed that can actually help, as opposed to passing around highly inflationary tokens (like people did with Doge) where the goal is to just get rid of them as quickly as possible, and it being no more of an empty gesture than wishing someone good luck.