Several recent court cases have resulted in small business owners, who create the wares and services that they sell, being ordered by a judge to sell their custom-made products (e.g., wedding cakes and floral arrangements) or services (e.g., wedding photography) to gay couples despite the small business owners' refusal to do so based on their religious principles.
If the business in question sold standard, mass-produced items, such as rings, then denying gay couples the right to purchase such things would be clearly discriminatory in the same way that a realtor would be discriminating if they refused to show a house that was for sale to any and all interested potential buyers. The sexual orientation of the buyers should not be an issue in that sort of transaction.
"Rightful liberty is unobstructed action according to our will within limits drawn around us by the equal rights of others. I do not add 'within the limits of the law' because law is often but the tyrant's will, and always so when it violates the rights of the individual." Thomas Jefferson
"If people can’t trust not only the executive branch but also don’t trust Congress, and don’t trust federal judges, to make sure that we’re abiding by the Constitution with due process and rule of law, then we’re going to have some problems here." - Barack Obama, June 7, 2013