Opportunistic commuters are damaging trade and angering shoppers by hogging free parking at the Stafferton Way retail complex in Maidenhead, according to staff.
Store managers say the busy car park is nearly full by 9am as drivers leave their cars at the site before returning in the evening.
The majority are thought to be London-bound workers heading to the train station.
But the situation could be set to change, with rumours that landlord CBRE Global Investors is set to install a new parking management system on the privately-owned car park to combat the growing problem.
Staff at the shops on the site say customers regularly complain about the lack of spaces available at the complex, with the issue becoming worse in recent months.
The busy site is being used despite the long-stay Stafferton Way car park next door having about 50 unused spaces per day, according to the Royal Borough.
Pets at Home manager Heather Lockley said shoppers having to carry cat litter and food bags weighing as much as 20kg were forced to park on the far end of the car park while Nikki Kaur, manager at Maplin, said the store had about 10-15 customers a day come in and complain about the parking situation.
A spokeswoman for the Royal Borough said train commuters are directed to use the Stafferton Way car park and season tickets are available for Stafferton Way, Nicholsons and Hines Meadow car parks for people working in Maidenhead.
CBRE Global Investors was unavailable for comment.
See this week's Maidenhead Advertiser for the full story.
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