sdcard volume mount - exists even when sdcard is ejected

[amitga]

Hello.
I noticed that the /mnt/sdcard/ and /sdcard/ mounts exists even when the sdcard is not inserted into the VOXL.
This came up when the root mount (eMMC) got full for some odd reason. I then noticed that the sdcard on the VOXL had popped out and my docker was writing stuff to /sdcard. This filled up the eMMC. This situation is a bit dangerous, because while you think you are writing to the sdcard, in fact you are writing to the eMMC.

I would like to know if there is a way to disable these mounts if the sdcard isn't inserted or happened to pop out (the spring on the sdcard holder of the VOXL is kind of weak).

Thanks