pawsplay said:(3) to distribute copies or phonorecords of the copyrighted work to the public by sale or other transfer of ownership, or by rental, lease, or lending;
IANAL, but I'm fairly certain that they did that when they sold the book to the bookstore. The store then entered into a civil contract not to distribute the books before the street date. Otherwise it would violate the first sale doctrine and would imply that Wizards had the power to stop me from selling my legally purchased books to a used bookstore for resale. While many companies would LIKE to have that power, current US law says that they don't have it.
The relevant bit is in Title 17, Section 109 (which modifies the bolded bit above in its first sentence):
Notwithstanding the provisions of section 106 (3), the owner of a particular copy or phonorecord lawfully made under this title, or any person authorized by such owner, is entitled, without the authority of the copyright owner, to sell or otherwise dispose of the possession of that copy or phonorecord.
The bookstore owns the copies that they've purchased. By first sale doctrine they can sell them whether Wizards wants them to or not. What may have been violated is a civil contract between the publisher and the retailer - an agreement to hold to a "street date" for sale of the book. The remedy would therefore occur in civil court, not criminal court.