Why the comparison usually goes wrong
Channels get compared on revenue and order volume, because those are the numbers both dashboards show prominently. Neither dashboard shows contribution margin, and neither knows your cost of goods.
The result is a familiar conversation: the marketplace is doing three times the volume, so it must be the priority. That can be true. It can also be true that the marketplace is doing three times the volume at a third of the margin, which changes the conclusion entirely.
What actually comes out of a marketplace sale
None of these appear in your revenue figure. All of them appear in your bank account.
- Referral fee, which varies by category and is the largest single deduction
- Closing fee, applied per item and weighted toward lower-value products
- Weight handling or shipping fee where fulfilment is through the platform
- Storage fees on slow-moving inventory, which compound quietly
- Returns processing, which is separate from the lost sale itself
What comes out of an own-store sale
Payment gateway charges, shipping, packaging, and the acquisition cost of the visit, since nobody arrives without being bought or earned. For a store advertising on Meta or Google, acquisition is often the largest single deduction, which is the mirror image of the marketplace picture.
The critical difference is that acquisition cost is a variable you control and improve, while marketplace commission is a rate you are given. A store that improves conversion rate lowers its effective acquisition cost. A seller cannot negotiate a referral fee.
How to model it properly
Take one product and build both columns side by side, all the way down to contribution margin per unit. Do it for a high-volume item and a low-value item, because the closing fee structure hurts cheap products disproportionately.
Then look at what each channel gives you beyond the margin. The marketplace supplies demand you do not have to create. Your own store supplies customer data, repeat purchase and no rule changes imposed from outside. Both are worth something, and neither shows up in a margin calculation.
Key takeaways
- Compare channels on contribution margin per unit, never on revenue
- Closing fees hurt low-value products disproportionately
- Acquisition cost is improvable, marketplace commission is not