How to get all users that uploaded avatars or have gravatars? [closed]

This function bp_get_user_has_avatar() calls bp_core_fetch_avatar with this argument 'no_grav' => true so you could write your own function to see if a user is not using the default avatar:

function lurie_avatar_check( $user_id ) {
    $retval = false;

    if ( bp_core_fetch_avatar( array( 'item_id' => $user_id, 'no_grav' => false, 'html' => false ) ) != bp_core_avatar_default( 'local' ) )
        $retval = true;

    return $retval;
}