Are these sentences grammatically correct?

I will read it and promise not to make any noise. I have so many things to be packed so take your time. Why are People Willing to Pay More for Wearing Famous Brand-Name Clothes? Consumers make a purchase when they associate certain images with particular products. Buying Brand X’s new jeans isn’t worth much, because each individual wastes his or her money. The store can make profits from sales clerks’ up-selling, and you could also benefit from it. Strategically placed inexpensive items attract and persuade customers to make additional purchase. Nobody forces you not to buy things that suit you, but think about the principle of item placement.