Special Permissions to save presets on Mac?

I made a preset browser for my plugin that can load, save and sort through presets on my Mac without issues. However, I distributed a beta and found that others were not able to save their own presets. Loading still worked, but I created the directory and dropped preset files off in an installer.

Do I need some sort of special permission to give my plugin file writing access to save a preset file within a specified directory on a Mac?