Keyword Advertising and Trademarks

Earlier this month, there was an intriguing legal case between 1-800Contacts and a competitor, Lensworld. The fight started when Lensworld bought keyword targets ads (such as Google Adsense and the ads that show on the right side of a search result) for 1-800Contacts, 1800Contacts and 1 800 Contacts. It's a common practise, but 1-800Contacts filed a trademark infringement lawsuit. It's not the first time, and I'm sure it won't be the last.
The problem is, the ad networks are set up to allow you to do that. You can purchase any keyword you want, even a trademark name. The opinion is wide and far on whether or not its ethical. Some contend that if you own a trademark and have spent the thousands of dollars to establish that name and brand, no one else should be able to benefit from it. Valid point! I don't want my competitors showing up when someone searches for Aloha Media Group. Their looking for me. But it's a common practise. Searching for brand names in google will easily show, a lot of people don't have ethical questions about purchasing ads for a keyword that is a trademark. And what about the search engines and portals? Where is Google on all this? Silent for the most part. They have built the infrastructure and have not put any restraint in for straining out trademarked keywords. And can you imagine the technological/legal hurdles to accomplish that? It's very thought provoking, and sure makes for great blog material. If you have an opinion about this. Post it now, we'd love to hear.