So what? If you plan to shut the relays down on a whim, why should people donate? If you plan to fight to bring them back if something brought them down, just not necessarily the same day or week, tell us so and we will not complain if it's down a day or two.

Also something being free doesn't stop people from complaining when it goes away, so it's all in your head.

I would prefer if you charged for things that are easy to charge for, namely relays. If people pay for that, you at least know why and when to scale them up. The zaps here should be for what's less constant and less directed to specific users.