Invitation to Embarrassment

As seen on a recently-received wedding invitation:

Réspondez, s'il vous plaît

...Only the verb répondre doesn't have an 's' in it as it does in English. That's what tipped me off to the fact that they were probably homemade invitations (and surprisingly well-done ones, at that). However, if it turns out that they were bought and paid for, well, she should demand her money back!