There are an quite a few adults in North America with the name Wendy. Dave Thomas named Wendy's after his niece and while Wendy's is a popular fast food chain I think it's stay as a name outweighs that - especially because of the popular character Wendy from Peter Pan, which most people become familiar with long before the restaurant.
"Chan eil tuil air nach tig traoghadh"
Capt. Malcolm Reynolds - Half of writing history is hiding the truth.
- Serenity