If we go through the history of Marketing, we will find that in earlier time only sales was there, then people started doing other activities to promote their sales..........
That was sales promotion.....
Then whole activity turned into marketing.
Today sales is itself customer focused and definition of sales is needed to be change, as now it is not only the transfer of ownership, it has become a tool to create relation and not only focused to mutual benefit but it also cares for the highest level of satisfaction.
In my view marketing is only the activity to aware and educate customer about the product and insuring the availability of the product in market. After that all activities done by any sales person should come under sales.