Ignore WooCommerce Membership product restrictions when facets are used on Shop page.

functions.php

<?php

/**
 * Ignore WooCommerce Membership product restrictions when facets are used on Shop page.
 *
 * @uses  FacetWP
 * @uses  WooCommerce Memberships
 */
add_filter( 'facetwp_is_main_query', function( $is_main_query, $query ) {
    if ( 'wc_user_membership' == $query->get( 'post_type' ) ) {
        $is_main_query = false;
    }
    return $is_main_query;
}, 10, 2 );