I'm going to guess that every single person on here will call green star polyps just that in normal conversation rather than the actual species name. Same thing with calling all Montipora plating corals as Monti caps (when they aren't all capricornis.) It's the same thing. I'd hate to try to figure out every single Acro I have down to the species name with 100% accuracy. Just not going to happen. I'm also not going to say, "I'd like to buy that blue and green Acropora tortusa" when I can just say, "I'd like to buy the ORA Tort".
Say you take the "pink lemonade" name off and just have it as some unnamed acropora that is yellow and pink. Guess what...I'm willing to bet that supply & demand will have both the "Pink Lemonade" and the "Acropora" with a good photo of each would sell for about the same price. No one in their right mind would sell a frag of the "Pink Lemonade" for the same price as a "Green Slimer". It is what it is - supply and demand. The more beautiful a coral is, the harder it'll be to get b/c everyone will want it...which means the price goes up.
Now, let's say someone out on the west coast of the US posts a picture of the most beautiful Acro. If you sent a PM to that reefer and asked what it was...without using "common names", guess how much luck you'll have finding that same coral out on the east coast. Probably not much. So-and-so reefer will call it Acropora Millepora with a kinda rainbow hue but with a blue growth ring, green polyps, and a reddish tip. Riiiiight...good luck finding that. Now, if that reefer told you that it was an ATL Sunset Millepora, you could look for people in your local area who have that. Makes it much easier.
A while back I had an acro that was absolutely my favorite coral. I'd never seen it before, got it, and due to a tank crash, it died. If it hadn't had a name, there is no way I could've tracked it back down.
I do have a problem with people who buy a colony, name it, hack it up, and try to sell frags for $70 each. I have no problem with people who buy a colony, grow it out, sell some frags here and there, people start loving the coral so demand goes up...so then the seller names it and charges more (since it's more in demand).
And lastly, if you don't agree with the naming of corals, just don't buy them.