This is just something valuable from Tether, where Tether can afford to be next to Celsius and work together on payment, even though the minimum cost to buy it is 50 USD.
But for those who have a lot of money, 50 USD is normal and not too big for business purposes.
I also see that this Tether Gold is pretty good, where Tether is comparing with the price of gold and it is certain that Celsius also understands this for future business.