This is a marketing gimmick. They are encouraging people to buy the coins but at some point the bubble will burst and people will be left with over priced coins. As a general rule if you buy a coin from the US Mint you wouldn’t make money (the coins will not appreciate) unless you hold it for 10 years.
This also may not be the US Mint but a company that calls itself US Min, you have to look carefully and there are just getting people to buy their coins and once they are all sold out they will declare bankruptcy. In that case some of the people who sold the coins back to them are out not only their money but also the coins as they are unsecured creditors.