You won't be able to dismiss this by usual means (escape or click button), but you can close it programatically based on user choices or actions.
"We debated adding Accommodations cards to our invitations since we have a website and assumed people could get their information there. However, I am so glad I changed my mind! These are perfectly matched to my invitations and they are the perfect size...about the same size as the response card. They shouldn't drive up shipping costs when sending the invites. I modified the card to say the name of our hotel block in the top box above the hotel information and used the bottom box (under the address) to include information about the wedding website. I love that someone edits each card personally to catch minor grammatical errors, etc."