There is no logical reason to prevent people from choosing to sell and advertise goods in imperial measurements only if they wish to do so. People should be able to choose not to use metric measurements, and people obtaining criminal records just because of what system of measurements they choose to use is abusive, contrary to basic freedom of expression and aside from anything else a waste of public money.
In 2001, Steven Thoburn was convicted of two offences under the Weights and Measurements Act 1985 for selling with scales not configured in metric measurements.
The same year, Colin Hunt, John Dove and Julian Harman were convicted under the Price Marking Order 1999 for failing to mark up good in kilograms.
I am suggesting that it should be legal for traders to use either imperial measurements, metric measurements or both at their own discretion without facing criminal consequences whichever option they choose.