Setting the home directory to a special device node file "/dev/null" sounds like a good way to shoot yourself in the foot, and I've never heard of this practice

Setting the home directory to a special device node file "/dev/null" sounds like a good way to shoot yourself in the foot, and I've never heard of this practice before. On Debian, at least, it seems like setting the home directory to "/nonexistent" is more common. For example, running "deluser" later could end up performing a "remove home" cleanup operation, and you certainly don't want to remove the /dev/null file.