Should I ask for more then 1 pound cash for appearing on "food unwrapped?"

This is not a criminal defense issue as tagged, but more along the lines of a copyright issue. I suggest that, instead of spending time looking for generic advice that will not be able to address your question in any meaningful way, that you seek out an intellectual property attorney and/or hire an entertainment agent to assist you in this matter. The studio currently holds all the power in the bargaining, particularly since this is a contest show, and you will need someone savvy on your side if you hope to have any chance at negotiating a better position for yourself.