Thanks DWF for the answer. I guess I'll consider it but not top priority at all it seems.
I don't know if this belongs here but I just received a pair of Carmina double monks and it looks beautiful. However, the sole of one side has this gap shown below. I don't know what to make of it but I can see the inside. Should I return them? I'm afraid water might get inside and mess things up.
In the long run, if this is left unfixed, then water and pebbles can find their way into the stitching channel, which will grind the stitching and the leather out. Furthermore, it's a defect. Return it.