I have yet to find an un-journaled filesystem that can be resized without data loss or intermediate conversions, and I'm wondering why that is.
Filesystems like FAT, for example, leave free space at the end of the block device; it seems pretty simple to me to just add more free space onto the end...
Edit: It seems that some filesystems, created without a journal, can still be resized. I created an EXT4 filesystem with
mke2fs -t ext4 -O ^has_journal /dev/loop0p1, grew the partition, and successfully resized it. I also created an EXT2 filesystem (which to my knowledge doesn't have a journal) and successfully resized it.
My current theory is that it's just a big coincidence that most filesystems without a journal can't be safely resized and most with a journal can.