I think basicaly the answer is might be but there is an element of VAT

depends where the cruise goes(not sure now I have read some of the HMRC notes below)

You also need to understand the "Tour Operators Margin Scheme" used for holidays and not many do(including me).
http://customs.hmrc.gov.uk/channelsPortalWebApp/channelsPortalWebApp.portal?_nfpb=true&_pageLabel=pageLibrary_ShowContent&id=HMCE_CL_000501&propertyType=document

Try google there are a few links

http://www.holidaytruths.co.uk/viewtopic.php?f=43&t=128179&p=1282961

there might be something here as well section 10 covers cruises.

http://customs.hmrc.gov.uk/channelsPortalWebApp/channelsPortalWebApp.portal?_nfpb=true&_pageLabel=pageLibrary_ShowContent&id=HMCE_CL_000161&propertyType=document

You will find that you do not pay VAT on Cruises as they are seen as being a form of transport rather than a holiday, so your cruise club is quite correct.
The easiest way to check is to look at your invoice, if it shows VAT then you have paid it, if it doesnt then you havent.
It may be the case that there is vat on the flight potion of a flycruise, but if it is an included charter flight it will be minimal as you are not really paying for the flight as such, it is included.

Thanks. I did not know that about transport not having VAT on. I learn something ever day

Hi, No you dont pay VAT on any holidays, i dont know why.. but its definate that you dont.