By the way, I can't find a clear answer to if they use cheaper robusta coffee as part of their blends. At home, I switched to store brand robusta after realizing my tastebuds had adjusted to the stronger taste. And I wonder if drinking Starbucks has contributed. Robusta has more caffeine.
The secret to Tim Hortons coffee tasting great is the freshness of the brewed coffee. But I do believe they use the more expensive Aribica beens exclusively.