couchbase-cli wants -c/--cluster but man page reads: "by default this..."

The man page for couchbase-cli cluster-init --help:

-c, --cluster
Specfies the hostname of the cluster to initialize. By default, this parameter is set to
localhost:8091 for this command. See the HOST FORMATS section for more information on
specifying a hostname.

When I ran:

./couchbase-cli cluster-init \
--cluster-username=Administrator \
--cluster-password=asdfasdf \
--cluster-ramsize=8192 \
--cluster-name="RBAC Demo" \
--services data

I got:

ERROR: argument c/-cluster is required