Lets all try to keep in mind that capturing accurate pictures is difficult. Some sellers/vendors definitely take it too far but its usually not that hard to tell unless they are very skilled. i personally am never going to buy a coral that is represented by a crappy picture, if its all blue and i can't see the colors or badly focused. so some sort of white balance correction or filter is usually necessary. Some people definitely have legit gripes about enhanced or unrealistic photos and getting scammed but their are also many others that are just hating because the coral doesn't look that nice in their aquarium for a multitude of reasons.
also keep in mind that not everyone even runs white lights anymore, so they may not be able to give you a "white light" picture. or they might have to reset/reprogram their lights to do so, so if its not a big sale they will probably not bother. especially when you go to all the effort to change your lighting schedule and take a bunch of "white light" photos, and they still don't buy anything.
the pictures below are a good example of the difficulty of taking representative pictures. They were taken with a cannon T3i, under the same lighting (radion ab+ program, with supplemental blue bar LEDs), within a few minutes of each other, using custom white balances on the camera. The one in the middle is almost spot on, but not perfect, to what i see when i view the coral. I still had to actually use a auto white balance correction in corel paintshop, even using the custom white balance on the camera. I had to take several photos and reset the custom white balance several times to get there.