I understand that many sellers do this. I work in the retail industry myself, and know every trick in the book to increase sales. Pushing my staff to "suggest additional merchandise" to customers and sell things up is an everyday occurence
What upset me is the bandwagon effect of the post, where everyone else jumps in to criticise the 'offender'. It doesn't make us look very good on this forum. Splitting groups up to increase profit as a topic is fine for discussion, but in this case all we are doing is indulging in petty put-downs.