And who ever uses their exact allowance? Either you use less and lose them or you use more and pay excess. I only ever hear of people trying use up their minutes, and telling me they feel safer with a contract because they know how much they spend.
I tell them exactly how much I spend a month on Virgin PAYG - between £1 and £5 a month, and I've never seen a contract that low.
I dont even think i hardly use my 600 mins 1000 txts on the O2 £30 web based tariff at all.