Why is "Appropriate Appearance" Important?

I'd like to open a friendly discussion. A few days ago I posted an opinion about the importance of maintaining a professional appearance when conducting any sort of marketing. Today I happened across a discussion thread on Facebook about rather or not a handler's appearance in a horse sales photo or video affects one's decision in buying said horse.

My opinion is emphatically YES! My response to the thread was, "Personally speaking, yes. [An unkempt appearance] is a turn-off to me. Especially when the advertised price is well out of range of what the photo depicts. I think people forget they are marketing themselves just as much as they are marketing the horse."

The latter part of my opinion, about marketing oneself, seems to be a point of particular contention among some of the other participants in the discussion thread.

Here are my thoughts on this:
Very few people care enough or want to take the time to look beneath the surface. There are many, many reasons for this, some which are valid, but not the point of the discussion. The point is that, in the
U.S., attractiveness sells. We often have less than 1 second to make a favorable impression with any advertising.

So give yourself every advantage!

If I were looking to buy a horse, I would think twice if the horse were presented to me by someone in torn jeans, sneakers, or worse, flip-flops and any old t-shirt. To me, the handler's appearance is a HUGE clue as to how well the horse has been cared for. If you tell me, through your wardrobe choice, that you don't care about yourself, then I'll make the leap that you didn't really care about the horse. The horse can be sparkling clean and the most conformationally correct animal in existence with three stunning gaits and fabulous jump, or spin or tolt or whatever, and I'll be waiting for a shoe to drop. I'll be thinking that he's too good to be true, that short cuts in care and training have been used. I'll be waiting for a negative veterinary find. Most importantly I will NOT offer full price!
(I emphasize torn jeans as presenting in jeans may be perfectly fine and even expected. Just please be sure they are neat, as clean as possible given that we're discussing horses, and well fitted.)

From another angle:
Due to the present economy I have been forced to lease my own horses. I have made sure that in my advertising, the photos and videos I used depicted myself or my friends in riding appropriate clothes. As we are Hunter/Jumper and Eventing riders, that meant we had on breeches and either tall boots or paddock boots and half chaps. T-shirts were either tucked in or fitted enough to be neat. Whenever possible, I used horse show photos to be safe. When my gelding went up on trial a few months ago, I showed him to potential buyers and lessors dressed in riding clothes. I did this for two reasons:
First, I expected to ride first, for the client to see how he went under saddle.
Second, he is a horse that I trained. I want potential buyers to know that I have the capability and expertise to ride and train horses. It opens up the potential for future opportunities for me.

Now, I realize I'm discussing the horse industry, which is tremendously varied in the number of disciplines and therefore what constitutes appropriate dress. My intention is NOT to put anyone down. Rather, I'd like to motivate you to think of yourself and what you are saying to a potential buyer, even if you are heartbroken at having to sell. If you think well of yourself and dress well in presenting your horse, maybe, just maybe good things will happen. In my case, my gelding was leased within a week of his ad posting and I had request for retrial by an interested buyer.