That's just how federation works. You've federated with an instance/user so now your self hosted instance will be updated.
Is there a reason you're concerned about the requests? The payloads should be relatively small, and unless you're running on some really old hardware, one request a second with a small payload should not have any noticeable impact.
They would still line up, wouldn't they? Or am I misunderstanding how the texture healing would work... Would they not take the same total amount of space?