Reasons to get a CWP, off the top of my head:
First, on principle -
1) Because you can, and in most places in this world that is not true.
2) Because the more permit-holders there are, the less likely it is that politicians will think Gun Control is a viable political platform.
3) Because rights not exercised tend to atrophy.
Next, for practical reasons -
1) It simplifies the issue of transporting a pistol to and from wherever you normally use it. (SC isn't difficult, but try transporting a handgun in an SUV in a state that requires transportation in an isolated compartment... and ask for local PD's interpretation of what that entails...)
2) If you ever find yourself in a scenario where you wish you could legally carry, you won't kick yourself because you haven't even started the application process.
3) Application costs, even if one includes a training class, are typically less than the cost of a pair of hiking boots, shorts, and a moisture-wicking shirt from REI, for example; for those who are less outdoors-inclined, the net cost is typically less than two or three dinner dates at a decent restaurant - and the CWP is good for several years.