In WooCommerce, make the online store notice only show up in store pages as opposed to the entire site, which is the default behaviour.

functions.php

if ( ! function_exists( 'woocommerce_demo_store' ) ) {

	/**
	 * Adds a demo store banner to the site if enabled
	 *
	 * @access public
	 * @return void
	 */
	function woocommerce_demo_store() {
		if ( get_option( 'woocommerce_demo_store' ) == 'no' )
			return;

		$notice = get_option( 'woocommerce_demo_store_notice' );
		if ( empty( $notice ) )
			$notice = __( 'This is a demo store for testing purposes — no orders shall be fulfilled.', 'woocommerce' );
                if (! is_woocommerce () )
                        echo apply_filters( 'woocommerce_demo_store', '<p class="demo_store" style="display:none;">' . $notice . '</p>'  );
		else echo apply_filters( 'woocommerce_demo_store', '<p class="demo_store">' . $notice . '</p>'  );
	}
}