Each channel has a specific purpose. This purpose is not well understood by the omnichannel community.
Let's go way back to the late 1990s, at Eddie Bauer. If we were selling a shirt, we found that core sizes sold well in physical stores, while extended sizes (2XL, XLT) sold exceptionally well in catalogs and online.
Some in the omnichannel community demand that you sell the same merchandise in all channels - they tell you that the customer "demands" that you sell the same merchandise in all channels.
Others suggest that you use stores as digital distribution centers - when the 2XL size is not carried at the Northgate store in Seattle, you fulfill it from Bellevue Square.
Ignore the tactics and opinions. Follow the customer.
A well-done Merchandise Forensics project illustrates unique customer differences across channels. I routinely find that each business possesses unique behavior - behavior that is different than what you are taught when reading trade journals, research reports, different from what you learn at a conference. Merchandising data by channel tells you, rather clearly, what your channel-centric strategy should be.
Or contact me now (kevinh@minethatdata.com) for your own, customized Merchandise Forensics project.