IBS sufferer here too, and I totally agree. I wish it could bulk things out with lentils, but it really is an absolute no-go.
For those blaming the government, it really is not just the UK, but it is a worldwide issue. I am in a SH hemisphere country and it us hit as just as bad.
I do think though that on top of this issue, many people are eating according to trends. There is so much information out there now about needing this, that and the other every day for good health and wellness. These include things like eating fresh berries every day, just for one example. Grinding up flaxseeds, or adding chia seeds to a daily meal as another.
These are pricy items, but these days are promoted as 'essential' on social media.
I have not eaten a single berry since April, until last week. Because April to September is not berry season. And I live in a hot fruit producing country, and we cannot even get these items out of season. We eat what is available seasonally, and really that is our only option.
I look at threads on here where a young parent has been absolutely annihilated on a thread as she gave her child a packed lunch of a jam sandwich, a yoghurt and an apple for lunch. The comments incoming are how dreadful jam is, the child is going to suffer long term damage because they were given sliced shop bought bread and yoghurt... well that is upf to the highest degree according to some. Then they continue to bully OP while listing what their child ate, which is 4 types of berries, a thinly sliced nectarine and prawn salad with homemade dressing.
So OP feels shit, next time she shops she buys 5 types of berries and a bunch of lunch food that they feel pressurized to buy. Cue Tesco's now seeing how many berries they moved, and order in more for demand.
So yes, food is going up everywhere in the world, but supermarkets are businesses, and if a product is in demand, they will supply it but hike the price as it is now a sought after item.
I am an outsider to what is normal on food threads here. I know not everyone gives in to this pressure, but I think many do.