Well do feel free to share a link with it at £50 delivered, I didn't put the full RRP price but 60 seems to be the going rate. If I were to consider cheapest whey/dextrose/maltodextrin I could find It would probably end up closer to £30, but I thought it was only fair to include something that can be done in 2 mins of Google in the comparison.
And you are very optimistic if you think it has anything more in it than the very basic ingredients, they would have shouted their lungs out if it had creatine, glutamine, HMB, digestive enzymes or anything like that. Instead they mention some lame ass vitamin C and E which you won't absorb much anyway.
That's how the supplement industry works, get basic ingredients, stick on a shiny label and sell it on as expensive as possible.
That's why the analogy with the BMW doesn't work - there you get a package of a nice car, driving position, reliability, build quality, brand heritage etc . So it's worth paying for it than trying to make it at home and ending up with it being a Kia.
But with the supplement industry -> you are basically paying a lot more to save yourself the hassle of opening one extra tub of powder - not the same kettle of fish.
This is of course my opinion, everyone is free to spend their money on whatever they like.