There are certainly some positive aspects of pitting warrior against warrior. It is an excellent opportunity to experience first hand different fighting styles. There is always something to be learned from others and there are few things as eye opening as being on the receiving end of innovative tactics. It is also necessary to understand combat styles if you plan to spend time in Felucca. At some point in Felucca, you will be assaulted by some of the less honorable citizens of that realm. The best way to survive this encounter is to be familiar with the tactics that would be used against you. There is much to be learned from consensual sparring. What I would argue, however, is that there is only one valid reason to ever attack an unwilling opponent. That reason is defense; either to protect yourself, or another individual.

Following are the reasons most fight against others:

1. Acquisition of goods: Fighting another with the hopes of getting equipment and/or wealth. This is the age old fallacy of Might makes right. It is the believe that if I can best you in combat, I'm entitled to your equipment. It is stealing, pure and simple.
2. Bragging rights: Despite town conquest, this is what Faction fighting centers on. All faction members track their total number of kills and routinely compare to see who has killed the most. This is vanity in its purist sense and it serves no purpose other than the self-gratification of the participants.
3. Political: Guild wars fall into this category. This type of fight is based upon the belief that others do not have the right to live as they choose, and they should adopt your style of life. There is never justification for the forceful subjugation of others. If your guild is under attack, then this would be defense and is justifiable. A guild should, however, attempt to avoid this scenario as accepting a declaration of war is to the detriment of its members.
4. Punish the wicked: This stems from the belief that it is possible to cleanse the land of wicked people. Alas, in these days of high magic and medical science, death is not a deterrent to those who plague our land, so there is naught to be gained by seeking conflict with them.

The ability to leave a sword in its sheath is perhaps the last and greatest lesson a warrior can learn. It requires discipline and confidence that the path you have chosen is correct. It is usually self doubt that brings a weapon to the ready. The greatest warriors are the last to bare a blade.