filesystem permissions using dump on live filesystem

[Aaron Peterson]

i put a user in the operator group in /etc/group:

wkstn% pw groupshow operator
operator:*:5:root,alpete

and attempted to dump a live filesystem:

wkstn% dump -L -0u -f /mnt/storage/incoming/dump_test.dmp /usr
/sbin/mksnap_ffs: Permission denied
dump: Cannot create /usr/.snap/dump_snapshot: No such file or directory

wkstn%

wkstn% ls -la /usr
total 58
drwxr-xr-x  20 root  wheel      512 Feb 14 20:32 ./
drwxr-xr-x  20 root  wheel      512 Feb 20 00:58 ../
drwxrwxr-x   2 root  operator   512 Feb 13 18:59 .snap/
 --snip--

wkstn% cd /usr/.snap
wkstn% touch test.tmp
touch: test.tmp: Permission denied
wkstn%

what am i missing here?