Its a fair question. If I were to speculate I would say they were buying habits. Specifically transportation habits. The closest analogy in my own experience is telephone directories. For all of my early life experience there where printed and bound telephone directories which you consulted when you needed to find the telephone number of someone you wished to talk to. There was a very profitable business in selling ads in the commercially oriented pages.
Google search changed that, over time it became easier to find a phone number online than it was in the books. Then with the smart phone it combined both the phone and the number database (search engine) into a single device and now very few people use phone books.
But that habit changed slowly, over a decade at least to go from early adopters to the majority of people out there using their phone (or the web) to look up numbers. So the habit for calling a cab is changing slowly. From regulated livery service to less regulated ride share service. During that transition Uber is apparently "spending" billions[1] to connect in peoples brains 'Uber' and 'rideshare' so that as ride sharing becomes the expected norm, people will think of it as Uber not "any number of ride share companies."
[1] It is an odd definition of spend, they are perhaps purposely under pricing their service (so subsidizing) in order to encourage use.
Google search changed that, over time it became easier to find a phone number online than it was in the books. Then with the smart phone it combined both the phone and the number database (search engine) into a single device and now very few people use phone books.
But that habit changed slowly, over a decade at least to go from early adopters to the majority of people out there using their phone (or the web) to look up numbers. So the habit for calling a cab is changing slowly. From regulated livery service to less regulated ride share service. During that transition Uber is apparently "spending" billions[1] to connect in peoples brains 'Uber' and 'rideshare' so that as ride sharing becomes the expected norm, people will think of it as Uber not "any number of ride share companies."
[1] It is an odd definition of spend, they are perhaps purposely under pricing their service (so subsidizing) in order to encourage use.