> In which situation does the end user not pay for everything? Even a fine or a tax on a company ends rolled up in the price paid by the end user.
New costs are covered by a combination of a cut from the seller's profits and an increase in the buyer's price, and the proportion of each varies greatly depending on economic factors.
For example, imagine you offer that ugly sweater in an online marketplace. Can you just charge whatever you like (cost + desired profit)? No way. You can only charge as much as someone will pay, and that may work out to be a loss - for less than your costs. If somehow your costs go up - you spill something on it and need to dry clean it - can you just charge more? You can try, but there's no reason buyers will pay you more because your costs have increased; they don't care. Now imagine an inventory of 1,000 sweaters to sell - you might get lucky with one desperate buyer, but it's even harder to raise prices when you need 1,000 buyers.
Companies sell some things for huge markups, such as a bottle of soda, and for losses - even if the cost is $500, $100 is better than nothing. Think of sales and clearance sales.
Like you, companies price things to maximize revenue, where R = price x volume. Theoretically, they already price things for maximum revenue before they incurred additional costs, so how can they raise the price?
One way is to shift consumer perspective by blaming X for the price increase - government is a popular excuse, or oil prices - saying they must pass on the additional cost, and persuading some consumers that they must or ought to pay more. But when they say that the new tax will have to be be passed on to the consumer, they are full of $#!+ - when they buy the CEO a new private jet, do they pass that on too? - because they also can and do pass on the cost to their shareholders.