When Seating Charts add-on is used, tickets shouldn't be offered elsewhere. Respectively tickets purchased apart from the Seating Chart add-on will not have seat numbers/labels associated with them since Seating Charts add-on can only assign a seat number. There are several things you can do to prevent access to the ticket as WooCommerce product.
First off, you can navigate to Tickera Settings -> General tab and withing the WooCommerce area you can set Hide Tickets option to Yes which will then remove all the products declared as tickets from your WooCommerce Store page.
Also, you can set Redirect product single post to an event to Yes which will result in redirecting to the event page even if customers somehow get to the single product link. If you enable this, you should then edit your event and un-check Show Tickets Automatically checkbox (to disable showing the tickets for that event on the even page) and place a seating chart shortcode to the content of the event page which will then load Pick your seats button. To conclude, you should use seating charts shortcode on any of your pages or posts.