I had something of a Proustian moment this week.

Sitting in a pub with friends scoffing a plate of mince and potatoes with a serving of marrowfat peas on the side, the memory of my mother's kitchen came into my mind in a sudden, unexpected flash.

As I savoured the novelty of this traditional dish its smell, flavour, texture and appearance (cooked with carrots and onions with plenty of gravy and not a hint of garlic) prompted all sorts of memories, not only of the family kitchen of my youth but also of my parents' and siblings' voices, my school uniform and the friends I was hanging out with at the time. Such is the power of food to evoke an emotional response.

My mince had been preceded by a bowl of homemade lentil soup, and would be followed by a dish of jelly and fruit cocktail with a dash of (joy of forgotten joys) Nestle's Carnation milk. But despite the fashion for recession-chic comfort food, this was not a gastro-pub. We were in The Star Bar, a traditional boozer in a shabby area on the south side of Glasgow.

The experience brought into sharp focus assumptions about how much the Scottish palate has changed over the past 40 years or so. Our lunch (they could have had an ashet pie or a sausage hotpot, but my friends chose the macaroni cheese) was exactly the sort of food that was common in postwar Scotland and right up to the early 1980s, after which we saw the advent of the wine bar and the birth of the celebrity chef. Yet, on a rainy Tuesday in 2013, the place was full; priced from £2.50, The Star Bar's three-course lunch is thought to be the cheapest in the UK.

In the trendy Merchant City a mile or so up the road from The Star Bar, one upmarket restaurant has a main course of mince and tatties on the menu at £13.60. The Michelin recommended Sorn Inn in Mauchline, Ayrshire, serves steak pie at £11 as a main. In London, Tom Aiken's new gastro-pub serves macaroni cheese at £7.50 as a starter, and shepherd's pie at £13.50.

This makes The Star Bar's prices seem all the more incredible – which is why I felt compelled to try it. Its owner Paul Marletta is quick to point out he's "no Jamie Oliver". He calls his kitchen staff cooks, not chefs. The food he serves is the simplest and the cheapest it's possible to source. "People scoff when they see it's only £2.50 because they assume it will be garbage, but you get a good plateful of honest home cooking," he says.

And here's the thing: apart from the frozen chips and breaded haddock, everything is cooked on the premises and prepared from scratch in the little kitchen. Even the rice pudding is cooked in-house with Carnation milk. Sausage hotpot, ham or turkey breast salad with chips and fish and chips are favourites among Marletta's loyal clientele – the majority being pensioners, bus drivers from the nearby depot, workmen and a handful of smart young things – and they don't like it when he tries to put on something more adventurous. When he introduced gammon steaks they didn't sell, so they were replaced with ashet (steak) pies.

Even though he is of Italian extraction, Marletta has never offered pizza because he can't afford to run a pizza oven, which burns upwards of £24 worth of electricity a day and would push up his prices.

Around 130 covers each lunchtime are served by one extremely efficient waitress, three cooks on rotation, and a kitchen porter to do the washing-up. This helps keep outgoings down. "Costa or Starbucks will have three customers and five members of staff," Marletta points out.

The price differential is doubtless down to higher business rates in the smarter neighbourhoods – and the sourcing of ingredients. I'm sure the more expensive dishes in upmarket gastro-pubs are made with locally produced organic beef, artisan cheese and freshly dug heritage potatotes which, requiring minimal transport, have a higher nutritional content and a lower carbon footprint, and thus tick all the right-on foodie boxes. By contrast The Star Bar's ingredients come from the fruit market at Blochairn, Corcoran meat distributors in Barrhead, local cash and carry outlets, and cut-price supermarkets Lidl and Farmfoods. Marletta fetches ingredients himself rather than having them delivered.He says he's always on the lookout for the most economical way to source and produce his food.

His customers say it's cheaper to eat at his place than it is to shop at supermarkets and cook at home. He's painfully aware that he has to watch what he serves. Otherwise, he risks having to charge £5 a head and over, and lose his customers to the local KFC or McDonald's.

He says he doesn't make a huge profit from the food but he's doing what he needs to in order to keep his business going in the face of competition from the all-powerful chains. Many would say he's keeping the home fires burning by serving old-fashioned food that is relatively high in fibre, and low in salt, saturated fat and calories.

It's said that "you pays your money and you takes your choice". And for this foodie at least, that's plenty of food for thought.

cate.devine@theherald.co.uk

Twitter: @catedvinewriter