Some banks now let you make a throwaway card number for a website you do not quite trust. If it leaks, you cancel the number and your real card is fine. Nobody suggests opening a new bank account for every purchase.
Addresses work the same way, and this is the part almost nobody is told: one recovery phrase, the 24 words your account's key is made of, can make as many addresses as you like. Those words are the recipe for an endless supply of them, each with its own balance, and none of them related in any way the public record can see. Two addresses from the same phrase look, to the whole world, like two strangers.
So one phrase covers every pile, and there is still exactly one thing to keep: the paper the words are written on. The addresses are free.
Nearly free. A brand-new address has to be opened on the network by the first transfer that reaches it, and that first transfer costs a little more. If a client is paying you a thousand, nobody will notice.
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