Elderly patrons in his community in Cowliffe, Huddersfield, said that they wouldn't have made it through the recent bad weather without Gurmail, describing how he used a sledge to deliver groceries to those trapped inside by the snow.
Huddersfield MP Barry Sheerman said he was "a much-loved and respected member of our local community".
Martin Race, operations director of Batleys, of which Gurmail was a customer, spoke of his sadness at the news. "This is as appalling as it is tragic," he said.
Gurmail's son Bobby Singh was a general manager at the company's Leeds and Sheffield branches until recently.
The store has remained closed following the murder, but it is expected to continue to be run by the family when it reopens. The 63-year-old, who regularly worked seven-day weeks, had been considering retiring in the near future.