Converted vans not welcome?

Has anyone ever had any probs with camp sites not allowing converted vans onto their sites?

Went camping over the weekend in my vivaro and a mates T4 which are both converted vans. They let us on as we'd booked and pitched before they realised but they said if they'd noticed they wouldn't have let us on their site

I wouldn't have minded but the site was more than half empty... It really made me feel like s**t