This seems like a misunderstanding of how supply and demand acts in the real world. I didn't say people weren't buying premium products at all - they very much so are. They're just not selling out at the insane rate everything else is. If anything this suggests that the inexpensive products would (assuming we were operating an idealised free market, which we're kind of not because stores are now attempting to limit purchases) become more expensive to match the premium products - but then of course the premium products would sell more (more utility for the same money) so things would balance out again.
Retail pricing logic suggests that brands would rather price relative to the baseline pricing anyway. It's more likely to be generally inflationary unless of course suppliers manage to meet the current demand and even if they do there's a big risk that demand will crash suddenly at some point which could cost the suppliers or retailers greatly as well as they overproduce items that never get bought and cost money to store. It's a big mess, really.