In cinema jargon this is known as product placement. This doesn't of course apply to all cars in the same manner. Luxury cars however have basically always been in great demand. This global publicity, communicated in part by subliminal means and partly by overt ones, is positive and important, because it reaches a wide section of the public quite often on a world-wide scale and, with repeats, this can even become an audience of several millions. These type of placements should not be confused with conventional advertising.
Advertising is targeted at potential customers, in other words, a previously defined target group.
Product placement goes far beyond this. However, precisely this last point is what advertising should do. The target group between 30 and 50 would seem to represent the most interesting group for BMW, but on average they don't tend to visit the cinema very often. However, on account of its social status, it is precisely this group which would present an ideal target for BMW advertising. They too are hardly reached by product placement.