For an average weekly shop I would agree that Turkey is more expensive than the UK now. Meat is exorbitant, a crate of efes is now 50tl, wines ridiculously expensive unless you buy the draino. then when you take into consideration the cost of household cleaning products, toiletries, washing powder etc . The only thing that is cheaper is fruit and veg. but it is very seasonal and even that is going up in price. I think the price comparison was based on living rather than being on holiday and whereas I could get a weekly shop for around 70/80 tl a couple of years ago that doesn't buy anything now. You can shop around, Bim, Tansas etc but the savings are minimal.
The cost of living in Turkey has rocketed, petrol 3.77tl a litre!!!