Loading plugin script only on required page?

You could try this, it should disable the script from loading on anything other than single blog post pages without having to edit your templates:

add_filter('addtoany_script_disabled', 'disable_a2a_script_except_on_posts');
function disable_a2a_script_except_on_posts($disabled) {
    if (!is_single()) {$disabled = true;}
    return $disabled;
}