Perhaps Shearings advertised different prices regionally.
A few years ago I met some people who were on holiday with National Holidays in Folkestone, paying just £99 for return travel from the Midlands, with 3 nights half-board, a day trip to Canterbury, a day trip to the continent, a discounted bar in the hotel and nightly entertainment. When I checked to see if I could get anything similar from East Anglia, I found that National Holidays didn't operate from around here and Shearings wanted about £350 just for a weekend break.