I have bought some of the snack type foods for Christmas, but have them in an Aldi bag in the loft
. I'd never be able to afford to replace everything if it was being eaten by the DCs as quickly as I bought it.
I have a lot of things (food, drink, crackers, Christmas essentials etc.) on an online order with Sainsburys for delivery on Thursday. Ideally, I would have them in the house by now, but need to wait until I am paid on Thursday to afford them. I think it's the same for a lot of people TBH.
Sorry, I didn't notice if you said how old your DCs were? Is the eldest old enough to be left "in charge" of the younger DCs in the car while you pop into Smyths? If you don't drive, is there anyone with a car who could drive you & wait in the car with the DCs? A friend maybe?
I know it's stressful but please try not to worry. Anything that is out of stock Santa could give an IOU for - I know that sounds a bit crap, but I had to do it with something for DS1 one year & he didn't mind at all. The toy came back into stock in mid-January and DS1 loved getting a "late" present.
With money being tight, I would just buy one main present for each DC and pad it out with a few very cheap items - stationary, felt pens, colouring books etc. always go down really well here and are available really cheaply at Wilkos, B&M or the £ shops.