My co-workers threw me a surprise bridal shower. Everyone brought in food for Cinco de Mayo.... it turned out it wasn't for Cinco de Mayo, but rather for my bridal shower. Everyone chipped in on a Visa giftcard. I've only been with the company for 2 years and the only other shower they've thrown was a baby shower. She wrote one thank you card and set it out in the break room for everyone to see. Is this an acceptable way to thank everyone, or should I fill out individual cards for everyone who signed the card? Its around 20-30 people.