Weddings are typically detail laden events. The bigger the wedding the more details exist. It is no wonder that wedding planners are so popular. One detail, that is easy to forget, are bridesmaid shoes. It might not seem like an important detail, until you line up for wedding photos.
Even an eclectic wedding has a theme to tie everything together. Your bridesmaids do not have to wear the exact same thing to match, but a theme will maintain cohesion. The theme can be a color or a style. Having your brides wear the same color shoe will maintain a theme even if it is not the same shoe. Similarly, the same style shoe can maintain a theme if the colors are different.
However you choose to maintain cohesion, make sure the style of the shoe matches the dress. You do not want your bridesmaids to wear running shoes with a dress, unless that is your theme.