Why did this workshop charge for an oil top-up before MoTing our Audi A4?

My wife had her Audi A4 MoT'd at the Halford Autocentre in Horsham, West Sussex. When she collected the car, she was charged £15 for topping up the engine oil. I called the garage and complained that she had not been asked for this to be done, but I was told that they check the oil before starting the engine for the emissions test and will refuse to carry out an MoT if they consider the oil level to be too low. My wife had driven the car there. The oil warning light was not on. Is this action an easy way to make money or are they correct?
They are correct and this is a sensible precaution that benefits you. If the engine had failed during the MoT test, you would be liable for failing to submit it in suitable condition and would be facing colossal expense to have it repaired. Normally, an oil warning light only comes on to denote a severe lack of oil pressure and the imminent demise of the engine. It does not normally indicate oil level.
Answered by Honest John on

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