Mounting Directories with bind & different permissions
The bind option is not a real filesystem and does not support the uid and gid parameters. Specify the user or owner option to get the desired effect.
$ ll /tmp/moo/ -d
drwxr-xr-x 2 root root 40 Jul 24 01:07 /tmp/moo/
$ mount /tmp/moo
$ ll /tmp/moo/ -d
drwxr-xr-x 42 jaroslav jaroslav 4096 Jul 24 01:05 /tmp/moo/
$ grep bind,user /etc/fstab
/home/jaroslav/tmp /tmp/moo none bind,user 0 0