Seller's choices can make them or lose them money.
This is an auction sale not a buy-it-now sale.
The seller gains by getting more interested buyers, and not pissing off potential buyers. So they earn X amount if the item sells for $20. They gain much more if they start a bidding war and the item sells for $40.
So, does "sealed" without photos make money or lose money?
Yes, perhaps prepackaged, ready to ship. But, I like to browse other items....
Let me close that "other items" page quickly before I get tempted.
Anyway, "combined shipping" helps the seller get more bids and sales, and it helps the buyer get better rates... maybe. Or, if it is free shipping, the seller makes bank, if they bother to take the time to repackage (SAFELY).
I'm not sure about demanding quick payments. For me, I'll browse a seller's other items until I'm done bidding, then send in the payment. Then generally go away and never see that seller again. So, if they want to keep me interested, then keep an open tab.