I realize we couldn't charge customers this way, but it'd be nice if we could add products to orders through automation to keep better track of inventory numbers for promotions and back-end management.
Potential use cases:
"Buy one get one free" promotions: set an automation rule to add the "free" product to all orders containing the target SKU
Relevant product samples and sample inventory tracking: set an automation rule to add different product samples to orders, using product type filters or pre-set groups
Packing supply management: add specialty packing supplies (extra packaging for glass, insulation and ice packs for temperature-sensitive products, etc) as a product with weights and dimensions, then set an automation rule to add them (and their weight/dimensions) to orders that contain products that need them.
this would provide better inventory tracking on consumable packing material
it would also reduce the need to weigh orders, which would help a lot with batch fulfillment: currently, if I need one icepack per box and icepacks weigh 300 grams, the only way to add that is to add it directly to the individual product. However, the typical order quantity for the product is 1-10 items, all of which can fit in one box with one icepack: if someone buys 6 and I have the weight of 1 icepack added to the weight of each product, then I've added an unnecessary extra 1500 grams to the order weight, which is a large increase in the shipment cost.
Box weights and inventory: adding these to the box entry itself is already in the "ideas" system and it'd be great if that went through as-is, but if we could create each box size as a product, add weights, and then make an automation rule to add the box "item" to every order that had the respective box size, that would be a pretty useful workaround