Is it normal to pay high prices for an oil change at a main dealer?

I was charged £52.80 for four litres of oil by a Suzuki dealer as part of the first year service of my Vitara. This seems excessive to me, bearing in mind that I can buy the same grade oil for £3 per litre in a local shop. Is there any reason for this, for example, is the dealer tied to using Suzuki's own brand expensive oil? Do you agree that it is too much or is it par for the course for main dealer service?
It's like buying wine in a restaurant. You can pay 3x the supermarket price.
Answered by Honest John on

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