Color morph refers to the coral's color. The coral above is a green with purple color morph. Some color morphs are more desirable in just about all corals. A brown frogspawn is not as desirable as an Electric Green color morph. And if you saw a bright purple with hot pink polyp Frogspawn, it would sell for a lot more than the Electric Green. Some color morphs of corals are more common than others. That's why I said the price can depend on the color morph.
As for wild Vs Captive. Most Captive corals a little more expensive than wild corals. You are paying more for some to care and raise that coral. You are paying more for a coral that's adjusted to captive life, and growing in a way that will survive in captivity. Some wild Acropora colonies have a hard time growing in captivity since they were used to waves crashing down on them, and used to being lit from a moving object in the sky. It's hard to simulate that in captivity, which is why Acropora's growth pattern is different in captivity. Many people pay 10.00-30.00 for a frag of a captive Acropora because they know it's track record, and know it will do well. You can find wild Acropora colonies for double that price, and they are ten times larger.
Considering that, I'd call that captive raised Acropora frag more expensive.
Same goes for almost all corals. zoos, LPS, SPS. You will pay more for a coral that someone raised up, rather than chancing it on a wild specimen. And you also take the pressure off wild collections by purchasing Captive raised.
Hopefully that helps answer some of your questions.
As for how I can tell a wild Acanthastrea from a Captive raised, it's from experience. I've grown many Acans from frags, and they do not look like that when they grow into colonies. Also, the dead spot on the base of that coral is normal for many Wild colonies of Acanthastrea.
Two years ago, people were questioning how someone could look at a coral and tell if it's Acanthastrea or not. Now, almost everyone can tell the difference because we has seen a lot of them. Same goes for wild Vs Captive. When you have seen a ton of both, you have a better idea of what your looking at.
But nobody's prefect. I could be wrong.