The Kirkland (Costco) brand is labeled as being a blend of Oak, Hickory, Maple and Cherry. My guess is they are made by Bear Mountain because their "Gourmet BBQ Blend" is Oak, Hickory, Maple and Cherry. That would be great. I like the Bear Mountains just fine.
Another clue is that Costco sells 40 LB bags of Bear Mountain "Gourmet BBQ Blend" on their website.