Don't sellers dislike this service?

There was some resistance at first but how can you tell between a sniping service and a manual, last second snipe?

R2

It is beneficial for both, buyers and the sellers. Some of the online auction systems attempt to discourage sniping by automatically extending the auction time if a last-minute bid is placed. This approach leaves all bidding open, and allows the bidders who are watching during the final few minutes to raise the bid, leading to a last-minute automated out-of-control bidding wars between bidders, which can extend the bidding time long beyond what the seller desired, greatly raising the final selling price.

Sellers are not crazy about it, but they have options like other venues (craigslist), and setting a reserve, or a high min bid.

eBay charges more listing fees if the seller uses the reserve feature or high min bid.

Lately, the problem for eBay has been keeping buyers and attracting new buyers. They don't want to do the auto extension of the auction complete time, or it could discourage buyers.