It's not a benefit that has materialized, nor is there a roadmap to materializing it. Segwit will not make buying coffee with BTC any less reliant on trusting centralized merchant services/exchanges.

Sure it has. The fact that Starbucks hasn't implemented it yet doesn't change that tens of thousands of transactions per day are occurring with BTC. It certainly hasn't hit Visa scale for daily use yet, but either it or another crypto will within the decade.

curious, where are these tends of thousands of transactions occuring directly from consumer to paying for a product at a brick and mortar location?

Let's not count bitcoin mixers and drug transactions.