I agree from the artistic point that using dealer photos isn't in the spirit of the thing. Having spent hours of my life happily looking for that perfect shot, it is very peeving to be beaten by a photo of a fish that wasn't even taken by the other member.
On the other hand though, the fish entered are chosen and bought for their beauty, so the whole situation is rather secondary. You can buy your prize by spending more at bettatalk or aquabid (if you are in the US that is !
) So to say it is unfair that the photo is entered with it, there is nothing to stop you from bringing round your friend with his pro camera either.
To turn it back again, if there is no issue about just buying beautiful fish, then the only remaining judgable thing is the quality of the photo. Else, all you are judging is peoples' ability to find and buy nice fish. Effectively the dealer photo is just an extension of the above principle. In spirit however I think we should take our own photos. Saying that this isn't a photography competition is fallacious. It isn't meant to be, but effectively it is inseparable from it. My fish look good, rubbish or fantastic depending on the shot. Some pics might win me prizes, others of the same fish wouldn't even get nominated. The photographic element is inseparable unless we all gather together with our fish in person to be judged. Until that time (and I think a TFF fish expo would be fun
), all we have to work on is the photos, and the skill of taking a good photo should be included, it being far more valuable than the skill of going to your local fish shop and buying something expensive, anyone can do that!
Beyond that, all I have to say is that taking pictures of your fish is fun. Doing it will improve your skills and when you get that kick ass photo it will make it all worthwhile and much more satisfying.