What is the function of Design in general?
Be it buildings, automobiles, appliances or websites, designers choose the shape, size, disposition, number and location of components in order to achieve maximum safety, effectiveness and aesthetic value. These three qualities, in that order, come from the roman book “De Architectura”, which states that “a structure must exhibit the three qualities of firmitas, utilitas, venustas”, meaning it should be firm (solid, safe, stable), useful (it should serve its function) and beautiful. The order is a logical one, since a beautiful object that does not serve its function is useless, and one that does at great risk to the user is not worth using. Allow me exemplify:
A hammer is a simple tool used for beating things (usually nails) with great force. If it had a flexible handle, like a Morningstar, it would allow the user to exert more force with the same effort, but with significantly greater risk. The current design is safe enough without sacrificing force generation or precision. If we were to make a beautiful hammer out of porcelain, it would be aesthetically pleasing, but ultimately useless as a tool. It could serve as a decoration piece, but it wouldn’t be a hammer anymore, it would be a piece of art, and the beauty would serve the new function (which would be simply to be beautiful).
The designer must work to achieve these three qualities, in this order. In the case web design, the page must be safe in the sense that it does not allow for the infection of the user by malware (something relatively simple); it must present the information it needs to present in a clear and accessible way, being the exposure of information the basic function of websites; and it should be aesthetically pleasing, so that the user is not turned off from using it or his eyes grow tired fast.
In the same way that a physician must care for the physical well-being of the patient, the web designer must make sure that the information on the website is easy to locate and access. To do otherwise would be incompetence. To do otherwise purposely would be unethical, in the same way as planned obsolescence of physical equipment.
As for actions such as including products on the costumer’s cart and pre-selecting options, the designer is taking steps to remove or minimize the user’s agency. This is disrespectful, and the designer knows so, because if someone took away the user’s ability to choose that company he would complain about the morality of the situation.