One store owner, who did not want to be named, said he had been too busy to contact his MP. "I feel really guilty about it, but I just haven't been able to find the time," he said.
With MPs preparing for the second reading of the Health Bill, this week represents the last chance to influence their thinking on the ban.
The retailers who had written to their MPs all reported a swift and satisfactory response.
"After the expenses fiasco, MPs will be desperate to show the electorate they are prepared to fight for them," one said.
Sylvia Winter, owner of Creaton Village Store in Northamptonshire said her MP had visited her store to see the problem first hand, just days after he received her letter.
See p13 for details of how you can make your protest.