That's a very good point. Nowadays just few cryptos can hold the demand transactions, but this crypto world is changing very fast and no one nows what´s going to happen in the next months.
Whatever crypto which will be used for Starbucks payments will be completely beneficiary for cypto world and it will be a huge step to world adoption.
Next big company to adopt crypto payments could be Amazon which was aready on the news about this few months ago.