LOL.
You forgot the pocket watch.
Really though, you have to think about what job you are applying for, find out what clothing is appropriate and go for it. Wear something you feel comfortable in.
EG. If you are going for store manager position, then absolutely, wear a suit. Conversely, if you are going for the shop assistant role and have been told "smart/casual", then a suit is definitely over the top and you may end up feeling (and then looking) uncomfortable during the interview.
Remember, the interviewers would be looking to see if you will "fit in". If you dress up in a tuxedo, hat, pocket watch, etc and talk with a plum in your mouth, then the interviewers might feel that you don't belong in their store.