Why is oil so expensive from a dealer for my Volkswagen Scirocco?

Within a standard lube service for my wife’s Scirocco, using 4.3 litres of Castrol Edge, the cost was £90.30 (last year £57.54). For my car’s oil change, I have been quoted £91.42 (last year £40.49) for 5.7 litres, which amount I can get from Halfords for circa £43 (all prices including VAT). I challenged the quote but was simply told that’s what the cost is. So, please, what’s going here? Should I simply supply them the oil or would I be charged ‘corkage’?
Typical dealer mark-up. There is no way the correct oil costs him anything like that.
Answered by Honest John on

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