I believe if certain boundaries are not crossed then domaining is absolutely ethical.
Well, that's true, but it begs the question ... if "certain boundaries" are not crossed, then almost any human activity is ethical. Each person must decide what those "certain boundaries" are.
In the case of domaining, I think - and I know I'll be loudly denounced for this - that a lot of parking is unethical. Why? Because the typical domainer's focus seems to be, "I'm making $xx per day from parking this domain", without really exploring
how that money is made.
For instance, if you have a good H1N1 / swine flu domain parked right now, you've probably got click money rolling in. But what are your visitors clicking on? Is it some scam that's going to cost them money for a worthless product - or worse yet, for one that harms their health? I just did a Google search for "swine flu", and among the ads that appeared were that several that looked suspicious - e.g., "Doctor's Life Saving e-book $33 - Prevent Infection Naturally" and "Home treatment and prevention Herbs for flu, swine flu. Learn How". I'd wager that the information these folks are selling is worthless and/or dangerous.
The only domain I ever owned that made more than pennies a day was a "stimulus checks" domain that I got for <$5 on eBay. The moment I parked it, it started bringing in $15-$20/day. I was excited - but when I checked out the ads that people were clicking on, many of them looked questionable/scammy. I sold that domain to another DNF member pretty cheap, in the hope that he'd get it into the hands of a worthwhile end user (I've had little success with end-user sales).
Some categories of products & services seem less prone to scams than others. Still, since anybody can buy Google ads, you never know what you're helping to sell, or how honest those sellers are. As a result of these concerns, I'm shifting more and more of my domains from parking to affiliate ads for reliable companies (generally Amazon - and some people may question the ethics of
that, since I'm helping put small local bookstores out of business).
Meanwhile, people who profit from "sin" domains - porn, gambling, & so forth - may not consider the personal & social consequences of the services they're promoting. Or they may excuse it by figuring, "These people were going to spend money on those activities anyway, so I might as well profit from it." (Or they may not view these activities as "sinful" ... "Even though most people who play poker online will lose money overall, maybe it's worth it to them for the entertainment", and so forth. But however small-L libertarian our views may be, how do we really feel about promoting more use of paid-gambling & online porn services?)
Sure, you can try to eliminate some of these problems by massaging your parked domains' keywords & so forth ... but how many of you really consider the
ethics of parking, as opposed to just the potential profits? (I'm not trying to nag or scold, just encouraging people to think about what they're doing.)
OK, bring on the outraged reactions ....