Not having a Mac for myself to verify from, but looking for other forum messages that talk about profile locations on a Mac, look in the following locations:
User profile area - which you already know:
/Macintosh HD/Users/Username/Library/Application Support/Adobe/CameraRaw/LensProfiles
Lightroom Profile area?
/Macintosh HD/Library/Application Support/Adobe/Lightroom/LensProfiles or maybe
~/Library/Application Support/Adobe/Lightroom/LensProfiles unless this is the same as the Users area, above
