What you'll note from this article (from the Daily Mail, but the quotes seem legit) is the source of the price rises is contested. The grocery store management

What you'll note from this article (from the Daily Mail, but the quotes seem legit) is the source of the price rises is contested. The grocery store management said -- somewhat vaguely, after being questioned about it -- that, yes, suppliers could be raising prices excessively. Then an "insider" said that actually it was the groceries that were doing it. The whole point with inflation is that nobody knows what future price-levels are going to be, so there's upward price instability. Everyone is trying to gauge how much to raise things -- and of course, they tend to overshoot, which leads to a higher rate of inflation. That's what makes inflation so pernicious, and hard to eradicate. It's not so much that a constant rate of inflation is damaging, but when increase become noticeable, people begin trying to anticipate it, and that increases the rate of change. You'll also see this in pay negotiations: you'll see more strikes over pay raises, but it'll be very hard for unions or companies to accurate gauge what the pay rate rise should be. It's not that unions are trying to "gouge" management -- it's that the consequences of demanding too small a pay rise is the same as accepting a pay cut. So labour demands more than inflation, which in turn tends to push up the inflation rate.