This is ticket scalping, pure and simple (selling a ticket for higher than its value. This is extremely illegal in the United States. This is also a posting promoting a private enterprise for profit on the internet, extremely unethical.
This person, like most such complainers, is uninformed. They are taking advantage of your physical and informational distance from the actual situation: (1) It's completely a matter of local law whether "ticket scalping" is legal or not. Many jurisdictions have no problem with businesses investing in "ticket futures" in the hope that the price will rise. In any case, it is not "extremely illegal". Murder is "extremely illegal", except when done on behalf of a government. Scalping is a minor crime when it's a crime at all -- like jaywalking. (2) Promoting a private enterprise for profit on the Internet is completely legal and ethical. The Transatlantic link is certainly open to commercial business. Now, if they'd said "...on the Usenet" then there would be guidelines to follow, which mostly include sticking to the topic and not posting repetitive ads. I think that a single ticket ad in the Grateful Dead newsgroup is not out of line on either count. Especially given the number of people who end up looking for tickets because of bogus Grateful Dead Ticket Service policies. (3) Individuals selling things in "garage sale" mode are exempt from any ethical or moral Usenet/Internet restrictions on "commercial use" anyway.
Furthermore, the people who are doing this are selling what are known as "taper tickets". These tickets are only available through the Grateful Dead Ticket Service via mail order. The reason GDTS does this is to help deter scalpers.
Scalping tickets is a perfectly legitimate business enterprise. Scalping Grateful Dead tickets is even a commendable activity, considering the hassles that the Dead scene puts you through to get tickets. Personally, I only go when some friend offers me tickets, since it ain't worth the bullshit of tracking when to order (via email list or polling their phone service), sending in money orders within half a day of then, and following all the little regulations about the size and shape of the envelope, etc. A lot of places that have little `protected' markets like this, are going to find out what a free market is like. Good. John