Venue lowers wedding price

My fiance and I are getting married in August and we booked our venue in January last year. We recently downloaded a new brochure off their website as I couldn't find my original and I noticed the prices are £30 per head cheaper in the new version of the booklet! I mentioned this to the venue and they made it sound like it was normal and the difference is because they now offer a smaller menu. I asked if this meant we would pay the lesser amount and they said no as we are on the old menu. I didnt think much of it at the time, but the more I think about it, it annoys me. We weren't offered the reduced menu - £30 per head less would save us around £2000! Is there any way I can contest this?