Well the US music industry is one of the largest out there, so that's why. Although I don't think it's right for them to try to break in the US music scene either, it also doesn't hurt to try and see the actual outcome for themselves instead of fearing it because of previous attempts from different people in the same related-field.
If they ended up not getting the success in their US attempt, as long as they keep being active back in their own scenes instead of ignoring their dominant scenes + keep trying to break in the US market, it should be fine.
On a side note (not toward you migger), the multiple versions of the same song is so typical of CCM...idk if I'll be able to enjoy all of them, but I already have some sort of idea the version with Snoop Dogg lol...