Our boat is a floating tacklebox. LOL! We bring it all and then some! Problem is, we like to try the latest and greatest, which often means stuff that's not even available yet. It's fun to try them all out.
In addition, when we're in a tournament, you just never know what will be THE thing that will get them to bite. So between the two of us, we're throwing a huge variety of lures throughout the day in order to "figure it out" (be it size, color, presentation, sound, etc). I'd hate to lose because we either didn't try it or left it at home.
Bottom line: being flexible is key, and having a lot of tackle on board affords a lot of flexibility.
Works for us!