Hi HisaDrug
I read your post and I have to say is very interesting
MP is not perfect and, more important, the customers are not perfect.
I didn't have big problems with direct delivery but I have some customers that don't read the INSTRUCTIONS and they do the thing that i say DON'T DO THIS OR THAT, clearly in the note card added in my products.
But a happy customer is a big advertising for your business. So, if i have to redelivery a product to change the bad attitude for a happy customer, i will do.
And, only for those customers that don't believe in MP, i have a in-world store where they can see and buy it
The black list is not a useful idea. They can back with an alt avi.
Have a nice day