Debris from the shattered wall rained down on the pavement below as the front of the car smahed a large hole.
Thankfully, no-one was hurt in the bizarre incident at the firm’s store in the upmarket Edinburgh suburb of Comely Bank, although the driver was taken to hospital to be checked over.
The customer car park is above the store and the driver appeared to lose control of his vehicle late on Saturday afternoon, one of the busiest periods of the week.
The 17-plate Ford B-Max, costing in the region of £16,000, hit the metal wall with sufficient force to knock a supporting beam out of place and dislodge several metal bars.
The front of the car was clearly visible through the resulting hole.
Emma Lougheed tweeted a picture of the aftermath, with the caption: “Full marks to @waitrose Comely Bank staff for their swift and calm response to this!”
She added that staff were quick to comfort bystanders, put out barriers on the pavement below and call the emergency services to the scene.
She said: “I was just on my way out of the store as it had happened, so all the staff were running round sorting stuff out and a few people were making sure those who had been outside when it happened were OK.
“I didn’t hang around, the emergency services were all bombing down the road as I walked home.”
A spokesman for Scotland’s Worst Drivers, who obtained the picture, said: “Luckily the structure held the vehicle from going further. It does not bear thinking about what could have happened had the vehicle gone straight through and fallen onto the ground and pedestrians below.
“Without any further information it would not be fair to speculate on the cause of this accident.”
A Police Scotland spokeswoman said: “”Police in Edinburgh were called to Comely Bank Avenue around 5.40pm on Saturday 5 August following a report that a Ford B Max had collided with a wall.
“An 85-year-old man was taken to the Edinburgh Royal Infirmary as a precaution and enquiries into this incident are ongoing.”