Whatever applies to bank account statements applies even more to Credit Card Statements.  In addition to intimating the status, Credit Card Statements are expected to generate customer action by way of payment etc.

AltaSigna manages creation, encryption, signing and distribution of credit card statements for large banks like ABN AMRO Bank and HDFC Bank.

A credit card statement is also a bill. As such, digitally signing the statement makes the bill complete and when accepted by the user, creates an enforceable contract between the issuer and the recipient.

Credit Card related communications form a major chunk of Phishing traffic on the Internet. A signed statement and the customer expectation that any communication from the issuer will be digitally signed help obviate this vulnerability.

Where the customer uses his statement as evidence for transactions with third parties, the signature helps establish the authenticity.