I added the following lines into my /var/lib/lxc/Debian/config:

lxc.cgroup.devices.allow = c 81:* rwm
lxc.mount.entry = /dev/video0 dev/video0 none bind,create=file 0 0
lxc.mount.entry = /dev/video1 dev/video1 none bind,create=file 0 0
lxc.mount.entry = /dev/video2 dev/video2 none bind,create=file 0 0
lxc.mount.entry = /dev/video32 dev/video32 none bind,create=file 0 0
lxc.mount.entry = /dev/video33 dev/video33 none bind,create=file 0 0

I can see the devices inside the container's /dev. But none of the apps seem to be able to work with them.