Prepackaged food changed but the really difficult issue to emerge affected retailers of 'loose weight' products. They needed to be reassured there would be an agreed cut-off date for their transfer from Imperial to metric. The retail problem was that metric prices would always appear to be more expensive than their nearest Imperial equivalent. Voluntary transferees to metric found themselves commercially disadvantaged. This is because viz.
Prices are correspondingly lower.
The issue of how best to explain the position to consumers dominated much of the Boards creative thinking. The product which brought all voluntary retail initiatives to a full stop was the experience of the floor covering and carpet retailers. Their 1975 change to sales by the sq. Consumers bought, in very significant volume, the apparently cheaper priced imperial version. Metrication of carpet sales entered into full scale reverse and the Chambers of Trade and retail associations pressed for firm Government leadership, i.e. compulsory cut-off.