You're making a number of assumptions, though.
First, it's not "A seller getting scammed by one out of a hundred buyers", it's one buyer scamming hundreds of sellers. Remember, by definition, a scammer is someone intent on nefarious and probably illegal actions, and it's unlikely such a person would be satisfied with just one victim. In my book, a bad actor is a bad actor, whether he's in the role of buyer or seller, and in either case, he could victimize hundreds of counterparts.
Second, you're also assuming there's some physical product as part of the transaction that requires physical delivery info. It's pretty common to sell something intangible - a coupon for a discount at an online store, a share of mining machine's output, or even just something delivered electronically, like an ebook. In cases like these, all the buyer and seller need to know about each other is their electronic address, whether it's a coin payment address or an email address. Both are easily created for single use, and easily abandoned or changed.
Given that, I'm not sure it's fair to assume the seller is more likely to be the bad guy.
I dont have to assume...I can just read all the posts here. I see far fewer "sellers" getting ripped off.
A bad person can more easily scam one product to several suckers than one person trying scamming several different sellers.
Why? It's been beaten into our brains that sellers are the trusted party. Buy anything from Amazon, NewEgg, or any online store; your sending money first. Now, untrusted, dirtbags assume the same role, ask (and recieve) money first, with no protection to the buyer. If your trying to scam many sellers, your going to be sending money. If you only have 10btc, you 'buy' 10btc worth of product and rip off every seller, there still only out 10btc. If you have 10BTC and sell 200 230GH Avalons on a group buy pre-order for 1BTC...well, the 'seller' makes a killing.
There's no other payment system that makes it this easy to hide. Even when your dumb enough to send money via Western Union Moneygram for a shady deal, someone still has to come into a physical location and sign for the money.
Therein lies the bias - you're assuming this forum is representative of the greater world. I don't think that's correct. This forum is an odd microcosm, a niche world representing the intersection of extreme geekery, extreme greed, and extreme philosophical or political views on both of those.
I've never assumed that the seller is the trusted party. The reason I'm willing to buy from Amazon, Newegg, and others is twofold. First, I have seen others use and recommend them (or I have used them myself in the past). Second, I have assurance as a buyer that if there's any problem, I can dispute the charges with my credit card company. Even on the days when eBay required mailing a check, I had recourse through my bank to stop payment on the check if I suspected something fishy -- and I did exactly that once, when I caught wind of a scam and saved myself several hundred dollars.
As a small online seller, though, the world is flipped. Credit card rules generally say that in any dispute or charge-back, the merchant is automatically responsible not just for the amount of the charge-back, but also for the associated fees and penalties. Buyer fraud through charge-backs is a huge expense for merchants, particularly small ones who don't have negotiating leverage to carve out a good deal with their bank or merchant processor. In fact, one of the primary selling points of Bitcoins and virtual currencies to merchants is that unlike Paypal and credit cards, it's not possible to do a reversal.
I'd also point out that even though we don't hear about buyer fraud on this forum, it's not correct to assume there isn't any. I'm sure we can get many of the bigger sellers here to chime in about how often they've had a dodgy buyer play games, or demand refunds claiming something is broken. More to the point, while a single seller can easily be identified as a fraud, it's much harder to identify a single buyer -- sellers don't have a single point where they can commonly post feedback, other than trust ratings, and I don't see them used that often. It can be enlightening to read the negative trust ratings of people you'd otherwise expect to be positively rated.