home delivery when paying for post?

when questioned if I mind if the seller keeps my post money  I'm happy to pay if the seller delivers... just wondering what others thoughts are on this situ:

 

bought a fragile item, it was hand delivered which I was not expecting....(i paid $13 post)...which I realise now they're kept.

advantages being no post office queues if not home, comes to me in one piece and earlier than would have got to me via post.

 

is this the way it works?

 

I sell too, and where closeby I have delivered but not for that amount of money...i'd be inclined to refund partial... but perhaps thats just me.

the item is nice.  the person was friendly. any comments?