More and more business is transacted over the internet, so that such has become a routine way to shop, but unlike shopping inside a physical store in which the price of merchandise is clearly displayed, and of which that price is not some sort of revolving door in which as you reach to grab that piece of merchandise, the price thereupon changes to something slightly higher; rather, it always remains the same to that posted price. On the other hand, pricing on the internet, is far more dynamic, of which, prices of a given product can change, even multiple times in a day, and therefore the price of such can be different than what it once was, previously in the day, of which sometimes that price movement is favorable to consumer, and sometimes it is not. Further to the point, just because a given item is in a consumer's cart, does not provide that consumer with carte blanche that the price cannot or will not change, but merely signifies that if the consumer purchases that product within a reasonable period of time, that the price will be so honored, although, such seems to be left up to the policies and particulars of each given internet seller.
What does seem unfair is when companies that sell both online as well as having brick and mortar stores, do not have a consistent price between the two domains. That is to say, for instance, that one's local department store has one price for an item that a consumer is shopping for, whereas that same department store's online persona, the price so posted is actually different. The workaround to allow such pricing discrepancies to be legal for these big conglomerates is that though both sites have the same name, they are not the exact same thing; basically signifying that the local management of a given store does NOT need to have the same pricing that is shown online to consumers, because they are in substance, not exactly the same, and therefore not compelled to price their wares exactly the same.
What also seems to be unfair, is the pricing inconsistency when one goes to an online site but has not logged in and has selected a product worth purchasing, only to find out that when one thereupon does log in to purchase the product that the pricing has changed in an unfavorable direction to that person. This seems to fall under false advertising, because that vendor has one price that is displayed through a generic search, whereas, when it comes to the actual purchase being made, the price is higher. The workaround for retailers for this, really comes down to the fact, that a generic search, of which, the internet does not know for a certainty the exact location of the person considering the purchase of a product, does NOT need to match what the price of that item is, within that specific locality, of which the purchaser is logged in at. In other words, the price for a given item for a New York City resident does not need to match what that item would sell for to someone in Kansas City.
Still, the fact that prices are so dynamic on the web, and appear to change, depending upon whether one is logged in or not, or other criteria, lends itself to very thing that appears to be happening; at least, from time-to-time, which is those slight nuisance increases in prices to the consumer, because the seller of such, perhaps through an algorithm or similar, believes that the consumer has made an emotional commitment to a particular product and will buy such, even despite a very slight increase in price.