Is bistro cafe a concrete noun?

Yes, the Word bistro cafe is a concrete noun, a Word for a physical thing.

A concrete noun is a Word for something that can be experienced by any of the five physical senses; something that can be seen, heard, smelled, tasted, or touched.

Note: The term 'bistro cafe' is aredundant use of Words, the definitions of 'bistro' and 'cafe' are basically the same, a small restaurant.