The quickest answer is "yes."  A business is a free enterprise and as long as they are not violating some federal discrimination law, they can refuse to sell a display product as a matter of procedure.  Many companies do not sell display items because they are used or abused by the general public, and as such, tend to be subject to more warranty or defect claims.  The only time that a business cannot refuse to sell is due to discrimination--for example, many companies used to refuse services for African Americans.  Federal legislation was passed to prevent that type of discrimination.  If you really want the product, consider visiting with a manager to see if they will sell the sofa to you "as is" with a waiver of any future warrant claims.  An alternative is to have them special order the sofa for you and have it delivered directly to your home.  If you still encounter resistance and you feel that the refusal to sell you the sofa is because of discrimination, consider filing a complaint with the business's corporate office or visiting with an attorney that specializes in discrimination complaints.