I don't see a legal issue there, unless the font is proprietary one owned by Sarah Palin's publisher.
In the U.S., a product’s trade dress is legally protected by the Lanham Act, the federal statute which regulates trademarks and trade dress.[3] Trade dress protection is intended to protect consumers from packaging or appearance of products that are designed to imitate other products; to prevent a consumer from buying one product under the belief that it is another.[4] For example, the design (meaning the shape, color, and arrangement of the materials) of a children’s line of clothing can be protectable trade dress,[5] as can the design of a magazine cover,[6] the appearance and décor of a chain of Mexican-style restaurants,[7] and a method of displaying wine bottles in a wine shop.[8]
Statutory Source
Under section 43(a) of the Lanham Act a product's trade dress can be protected without formal registration with the PTO.[9] In relevant part, section 43(a) states the following:
“Any person who . . . in connection with any goods or services . . . uses in commerce any word, term, name, symbol, or device, or any combination thereof, or any false designation of origin, false or misleading description of fact, or false or misleading representation of fact, which . . . [i]s likely to cause confusion, or to cause mistake, or to deceive . . . as to the origin, sponsorship, or approval of his or her goods, services, or commercial activities by another person, or . . . in commercial advertising or promotion, misrepresents the nature, characteristics, qualities, or geographic origin of his or her or another person’s goods, services, or commercial activities, shall be liable in a civil action by any person who believes that he or she is likely to be damaged by such an act.”[10]
This statute allows the owner of a particular trade dress to sue an infringer (a person/entity who illegally copies that trade dress) for violating section 43(a) without registering that trade dress with any formal agency or system (unlike the registration and application requirements for enforcing other forms of intellectual property, such as patents). It is commonly seen as providing “federal common law” protection for trade dress (and trademarks).[11]