Depending on facilities and turnover in the licences premises, real cider is usually served from a polycask or similar container on or behind the bar.
Lately there has been an innovative marketing of real cider from Manucubes or a bag in a box system to extend the shelf life to 3 months. These are available from specialist off licence shops & are increasingly being used by Weston's. Both Manucubes or the bag in a box system are similar to the well accepted Australian wine box & prevent the spoiling of the cider by excluding air, thus preventing airborne anerobic bacteria infecting the drink, or if present, growing in the container thus making the cider "hard" (or infected) once opened.
(c) CAMRA, The Campaign for Real Ale.