Marcuse is using "classes" more in the traditional sense, social relations predicated (roughly) on ownership and control of society's gross productive capacity. But the point still rings true - in terms of media, for instance, there is a huge amount of overlap between what the "upper classes" and "lower classes" enjoy. Marcuse would have been very critical of the lifestyle and art produced by the culture industry today (see, for instance, his discussion on the sadness of seeing Freud in the drug store and Bach on the radio in the kitchen).