Positives(?) of selling
1- Rare shows may emerge for sale but later are "liberated" for trade whereas they were unavailable before. Even a jerk taper who wants to profit off their recording is still adding a recording to the overall pool. If you got rid of tapers who sell their shows you'd be losing shows that eventually circulate. They still in the end create something useful out of something bad.
2- As quickly as they can sell the show someone can buy 1 copy, torrent it, and kill the demand for it.
3-It give newbies an opportunity to get something they would otherwise NOT have the opportunity to get. (ie they have no trade material, burner, time, etc) Lot of the time the first time buyers are unaware that there's even a niche for this stuff or that it exists!
4- Lets face it its better than selling copies of liscenced material. That's TRULY ripping off the band as those recordings CAN be purchased and give money to the band. Live bootlegs by nature are stuff that ISN'T available for sale. If the band isn't releasing live recordings like the Pixies or PJ then there will be a black market for this stuff.
5- Selling truly reflects demand for a show. People will only BUY a show if they "can't" find it elsewhere ort don't know how or if a show is desirable. If it starts bids at $1 and ends at $30 is it the sellers fault or the buyer's fault? Personally I've be tempted to buy Smiths dvd's if I could get them at a reasonable rate (like $5-8). If sellers sold at a cheaper rate ($5 a dvd vs $20) would people complain?
Negatives:
1- Obviously no one SHOULD be selling bootlegs. Its the most obvious rule the trading community has. You really can't argue that its somehow okay to do. The band has said its okay to share but NOT to sell, so don't. Your giving the finger to U2 if you do sell.
2-Too often what the seller WILL get will be a show that was easily available to download, be possibly mp3 sources or TAO, and possibly a horrible sounding recording hyped as a good one.
3-If they have the ethics to sell they just may have ethics not to even send the show. Worst thing is a seller who won't even DELIVER!
4-I've noticed several U2 traders that have "selling rules" and a few traders who were former sellers. Its quite unfortunate that these guys are allowed to even host their websites. If the record label, webhosts, ebay, fans, or traders allow them to stay in business (even after possible multiple attempts to shut them down) then where's the hope of it ever changing? If the record label dosen't care or prosecute than its hopeless battle. If fans look the other way at a prominent seller just becuase they have a big collection then they are part of the problem as well.
5- Often shows are sold BY second-hand parties. Imagine if you were the taper of a show, traded it, and it ended up on ebay. That's a big reason why many tapers DON'T share with the masses. Thus selling in these cases has REDUCED the amount of future recordings to surface from a particular source. STG and hubs also INCREASE the possiblity of selling by making it easy to get shows for free! As soon as it shows up on STG then it often shows up on ebay!
6- Silver-pressed cd's are often made BY criminal organizations. I remember KTS and the "glory days" or bootlegs but really these guys who mass produce silver cd's are the ones REALLY making the mass profits. You don't want your money going to the mob just because they are better organized!
Weaknesses of trading:
1- B+P's by nature (1 for 1) don't reward the copier. They are a great way to give charity to the fanbase but really are a pretty rare occurance. They pay for costs but give no extra benefits or "profit". Is it "ethical" to ask for extra blanks.... is that profiting? Some people will argue that it is, some say its okay. Its certainly a grey area and therefore many won't help because it not worth their while.
2. Trading and taping by nature is money going out the door. Burners, equiptment, blanks, cases, ink, binders, shipping, all cost money. By nature there is no money coming in. Not defending selling to recoup costs, just saying its a rather crappy "business" model.
Sorry if I over-elaborated a simple argument. Selling still sucks!