After checking a number of launchers in the CC, it seems that it displays icons at 32 px but the ones that you point out have no 32 px version in the icon theme, so it uses the 48 px version.
Not sure why some common sizes are missing, especially if they were in previous versions of the theme (I haven’t checked this). or maybe the CC used to scale them before? If it’s an issue with the theme itself having removed icon, it would be an upstream bug in the parent theme (Humanity), though.