They are different divisions of the company, and that is why you can have three prices for one item (Catalog, internet and TDS). The whole thing is poorly run IMHO, but TDS will honor the catalog price if you ask. Just talk to a manager and they will do it (I'm a CM, I know). The catalog advertises the stores and the website because they are all in the same parent company.
mforbach, did you call the catalog or the internet help number? It would be nice if they would honor each other's prices, but we haven't heard anything about them having a policy similar to TDS.