@Romeo Fabulini,
Concrete, white lines to define parking spaces, cars, people etc. all surely do exist.
Combine them all together and you get the concept: 'grocery store parking lot'. A concept is a combination of characteristics which we use to 'get along' with one another.
I am suggesting that what 'you' (the collective you) experience during your time standing on the concrete, looking at other people, seeing the cars pass by and also noticing that horrible parking job by how badly she missed the clearly white lined parking space - during all of that happening (direct experiencing) - all you're (and most people) are experiencing is the concept 'grocery store parking lot'. Or rather, you're sure to continue to say to your 'self' - "I am in a 'grocery store parking lot.''
Because most people are sure to keep their 'minds' (even when other people aren't present) in a state which is always extrapolating some 'thing' which is empirically verifiable (grocery store parking lot). Take a look at the responses I've gotten to my initial assertion. Does it not baffle anyone how quick everyone is to defend 'grocery store parking lot' (a mere idea)?