Earlier quoted context omitted.
> What are the incentives for running a node? It costs my ISP resources but I pay a flat rate. That would have value to me.
if enough customers of the ISP do this, they will no longer charge a flat rate. It's just that some people manage to consume resources that other customers don't atm.
I’m confident it’s not an efficient market and they’re charging what the market can bare, not a tight markup over their actual costs.