Competition is one thing, unfair pricing is another. If the discounts are excessive, it erodes the brand's value and pretty soon, high priced items become the modern equivalent of Sony TVs in the '70s and '80s- they were advertised at or below cost, to get people in the stores, so the salespeople could sell something else at a profit. The joke at the time was "We lose money on every one, but we make it up on volume!".
It also seems that people aren't aware of the label that shows the intended destination for the products- it's not very large and has an A, E, U, J or some other designation and if something with E is sold in the US, they won't usually honor the warranty because it was supposed to go to Europe. This is called 'gray goods', which is a step away from 'black market'. This was a huge problem in the late-'70s and early-'80s, when small electronics like the Walkman were being shipped to different countries, around the standard tariffs and duties.