On-call at home should definitely pay less than active duty. That way, when a call comes in, the annoyance of being interrupted is offset by knowing you're getting paid more for responding.
If you get paid the same, responding to a call just becomes an annoying interruption ("I could be at home making the same money if this person I'm helping had just been more careful!"), leading to a worse experience for everybody.
If you get paid the same, responding to a call just becomes an annoying interruption ("I could be at home making the same money if this person I'm helping had just been more careful!"), leading to a worse experience for everybody.