I'd be interested to see an update to this study in the coming years. Starbucks has been pivoting towards take out and mobile orders and removing tables and chairs entirely from some of its stores lately.
If neighborhood entrepreneurs would benefit from seating, cities can require a minimum number of chairs per square foot, starting with a non-zero number to address US Starbucks locations that have removed all chairs.
Or they can just get rid of Euclidean zoning and allow people to create small commercial enterprises in their actual neighborhoods so actual neighbors can easily spend time there.