It may be excessive, though. Not really auctioning, either. But it seems like most people here aren't bothered by it.
I would wager that the people bothered by it actually use the marketplace and that's why it's an annoyance. The rest don't, and that's why it's not. It seems excessive to me too, but when I used eBay I didn't blame the idiots listing 1000 of the same item, I blamed myself for not using better search terms.