At risk of red text being unleashed, some retailers use .97 prices to indicate a product that was being discontinued. At DSG (Currys/Dixons) stores this was the case back when I worked there... speaking of which I've almost brought us back on topic again, as I'm quite surprised at that retailer's continued survival. They seem to be an unofficial showroom for their online rivals as much as an actual shop these days.
Indeed, DSG stores did use the pence to tell staff 'hidden' information (obviously these days such things aren't very well kept secrets) which was clearly more designed for the staff asked to give advice, and as such the person giving the honest advice would know which products to try and push that little bit harder!
As for how they still exist, well in recent years their pricing has actually been quite competitive and comparable to other online sellers, and while they do sometimes have their own unique SKUs so you can't really compare (as the product might be virtually or even literally identical, it will come in a different package so you can't actually price compare because nobody else sells that specific version).
Also, if you want something right now - as a lot of people do even if they spent days/weeks deciding on what to buy, it's great that you can order online and drive to your nearest store and, if on a retail park, can have someone bring the item to your car without even having to get out (bar to open the boot).
It helps also that Amazon in recent months has got somewhat less competitive, and their own delivery people seem to be getting ever more like Yodel or Evri - which isn't great if you decided to order something big and expensive. I think poor deliveries has perhaps played a part in making some people prefer to actually go out and pick things up, so having a good bricks and mortar store might actually be a positive again (and the store is also a warehouse for local online order pick-up/delivery).
Argos is particularly good in that they'll let you collect at your local store in a few hours, and then go fetch it from a bigger store further away so you aren't wasting additional petrol/time. If someone can get something the same day, that's a real benefit even over free next day delivery. As I said above, when you decide you want something like a new TV, chances are you want it now! Tomorrow is like a decade away.
(I think this is still on topic, albeit giving a reason why I don't think this particular retailer is in any immediate danger).