Why doesn't suid show in mount command for nfs mount?

Issue

• Our RHEL6 server mounts NAS with these options.

-t nfs -o rw,bg,hard,nointr,noac,rsize=32768,wsize=32768,tcp,vers=3,suid,timeo=600 nas01:/export/dir /path/to/mount/point

• However, suid doesn't show by mount command. Why?

nas01:/export/dir on /path/to/mount/point type nfs (rw,bg,hard,nointr,noac,rsize=32768,wsize=32768,tcp,vers=3,timeo=600,addr=xx.xx.xx.xx)