In dry(ish) weather shoes tend to go under the van, and in wet weather they sit on the step inside the van. That said, we usually have the drive-away awning set up for anything more than a single night, so there's loads of room to store shoes in the dry between the van and the main section of the awning. I can definitely see the merit of a plastic box though....
Definitely kidding....never travel without a full week's supply of wine, even if that requires a trailer! Just imagine..... camping.....without....wine.....