GMB union members at the Martland Mill JJB Sports warehouse in Wigan held a 24-hour strike on Tuesday and another on Thursday of this week.
The workers have started a work to rule and a continuous overtime ban.
The action involves 266 GMB members, the majority of which are warehouse workers and clerical staff.
GMB members want everyone working in the warehouse to receive the same basic wage, which would be topped up by bonus payments.
Company founder and director Dave Whelan called the union’s suggestion “barmy” saying, “It’s the communist way - cuckooland!”
GMB regional officer Sandra Blight said, “It is not just about the 3 percent pay rise. The issue is equality in the workplace.
“Everyone in the warehouse is on different rates of pay. What they want to achieve is one basic rate of pay.”