Humans as a species have been consuming dairy products for nearly all of that time (ok, some culture may not have just to clarify). Fats are important in the human diet, regardless of lack of fibre. Do we dismiss other foods as they are not "complete"? No we do not, we eat a range of foods in order to get what our body needs to function and be healthy, There is nothing wrong with cholesterol in moderation and there is in fact good cholesterol which our body needs Saturated fats have since been found to not be a major problem in our diets, it is the trans fats that are the problem.

I do think the whole whether we should be eating meat or animal by products is probably better for another thread so this one does not get off track.