If you have a Bytes instance (for example, from data received over the wire) and you need to parse an enum out of that, you first need to convert the Bytes into a String, which involves 2 heap allocations: the String itself and its buffer.
If we could instead parse enum values directly from Bytes, this operation could be very fast.
This issue came out of this discussion, where I'd used a StringPool to avoid the String allocations.