The basic point is a customer is not really saving any money by putting 12 'cross' seams in a room. They are basically getting bad advice from a GC, or a salesperson. If the only way they can afford the job is to put that many seams in a room, the salesperson, should show them a less expensive product. I worked for one guy he sent me out with a 12' x 27' piece of carpet to install in a room that was 9' x 27', i billed him for 36 yards, he paid me for 27 yards of labor. I never worked for him again. ( do you really think he sold the customer 27 yards of carpet, or did he sell the customer 36 yards of carpet, do you really think he sold the customer 27 yards of pad and 27 yards of labor?)
What some people fail to comprehend here, is the Installer is ultimately responsible for how the job comes out. If the customer wants 12 cross seams in a 13 by 13 room, I am not doing the job. If they want to pay me for the extra time, I will consider it, but for the most part it is not worth it. Good business sense, is the ability to tell the end consumer, how the job should be done, we are the Pro's, not them. Is their input valuable, yes, until they decide to rearrange their furniture, and suddenly have complaints.
In the long run the extra dollars a customer pays to have the job done right the first time, makes up for the many dollars YOU will pay to go back again and again.
While I am thinking of it, I did work for one guy who got so tired of pole marks, he added 18 inches per cut, all he had to do was show the customer the crush marks and they would pay for the extra material.