The Why
When a catalog is being used for both ads and FB/IG shops, any products uploaded to that catalog can show up on both. Meta will simply take the product data that has been added to the catalog and run them across both. This is because it pulls the products from the catalogs themselves, not the feeds supplying the products to the catalog.
Remember – Feeds just upload products to your catalog.
Ads and Shops use the products that have been uploaded to that catalog.
As Marpipe works by uploading the creative treatments as additional product images in your catalog, Meta can pull those additional images into the product pages on FB/IG Shops as well. While this outcome won't impact performance, it can be potentially be seen by some users as not an ideal experience. Below is a possible option you can take in order to mitigate this experience.
Create two separate catalogs
Note: This recommendation does go against Meta's best practice of one catalog per brand and can potentially impact ad performance
Pros: Explicitly manage shops and ads as separate strategies; run a stronger organic social presence; run Marpipe treated ads directly to your website only for conversion tracking
Cons: Cannot run catalog ads to Meta shops; new catalogs have a warm up period in which they need to learn which products will perform best in ads (approximately 30-45 days of gathering product event data)
You have the option to create a separate catalog in order to run your ads and shops as separate funnels. Doing so will prevent cross contamination between Marpipe and Meta shops.
Simply create a new catalog in Meta and upload your Marpipe output feed as the data source in this new catalog. When creating ads in Meta, you'll select this new catalog instead of your original.
Alternatively, you can set this new catalog to be your primary for Shops and leave your original catalog to run ads with. If you prefer this option, you'll need to remove your original Meta shop and build a new one around this new catalog.