Non-canon (as far as I know) but the only reasonable explanation is that replicated matter is not the same as ordinary matter at the quantum level. A replicator can "recycle" replicated matter, turning it back into energy - but cannot do the same to ordinary matter.

(If a replicator could turn ordinary matter directly into energy, and back into a different form of matter, there would have been no reason for rationing.)

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Non-canon (as far as I know) but the only reasonable explanation is that replicated matter is not the same as ordinary matter at the quantum level. A replicator can "recycle" replicated matter, turning it back into energy - but cannot do the same to ordinary matter.

(If a replicator could turn ordinary matter directly into energy, and back into a different form of matter, there would have been no reason for rationing.)

Compare this answer.