I've noticed this with tea, as well. Few places are willing to splurge on the higher marginal cost of the really good stuff. Why serve TWG (US$1/bag retail) when Twinings (US 4-10 cents/bag) does the trick? There's little rhyme or reason in the pricing, so you can sample 4 places charge $3.50 for a cup of tea, and get 4 vastly different (in wholesale cost and quality) teas.

With coffee, I am reasonably convinced that I am just getting Nespresso or K-cups in many places that aren't hipster cafes. If I go to Hipster Cafe here in HNL, I get Coava or Four Barrel coffee 2 day air freighted from PDX or SFO ground fresh. Cost: $3.50 + tax. If I go to a diner, it's $2.95 for instant coffee.