There are many scenarios where it can be useful, but to address what seems to be your main concern; you could simply restore and then only read at ALL until your repair completes.
If you use snapshot restore with commitlog archiving you're in a better state, but granted the case you described can still occur. To some extent, if you have to restore a snapshot you will have to perform some kind of repair. It's not really possible to restore to an older point and expect strong consistency. Snapshots are also useful for creating a clone of a cluster/node. But really why are you only restoring a snapshot on one node? If you lost all the data, it would be much simpler to just replace the node.
