For completeness:
So yeah there isn't much of a deterrent, yeah the seller has to relist and gets a refund on any fees and it just wastes time but I would doubt the random trolling is going to do much of anything to most people.
When a member wins an item, or uses Buy It Now to purchase an item, they must complete the purchase by sending full payment to the seller within 2 days.
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Unpaid items are considered a violation of our buying policies. All unpaid items are recorded on a buyer’s account. Buyers who have excessive unpaid items, or cancelled transactions, may have limits imposed, or lose their buying privileges.
So yeah there isn't much of a deterrent, yeah the seller has to relist and gets a refund on any fees and it just wastes time but I would doubt the random trolling is going to do much of anything to most people.
Unpaid item policy
Buyers must pay for the items they purchase on eBay within 4 calendar days.
www.ebay.com