Sanitarium has dropped Weet-Bix from the Warehouse stores, blaming supply issues.  

The Warehouse Group is questioning why only its stores are affected and the Commerce Commission is looking into it.  

Massey University marketing expert Bodo Lang told Tim Dower that it's unusual to target just one retailer.  

He says it's something we don't see very often, and the way Sanitarium has handled it doesn't help as it hasn't clarified why only The Warehouse has been shutout. 

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