They do it, because they can. Like everywhere else, instead of a reasonable profit, they want a humongous one.
During covid the for boiler cover that all energy companies have, was still being paid, hardly anyone had their boiler serviced, all staff were on paid furlough, so all these companies were just getting free money a huge amount. Last year they made profit of £256 million, £4 million more than last 2019, that's after losing 122,000 customers, purely as people were paying and not getting a service, due to Covid, the get of jail card, yet the policies still rise in cost and no refund given. It's all a joke.
The manufacturing, travel etc of say pasta, went from 29p to 75p. There is no way it can be justified, but they see it as a staple and they know it will sell, regardless of the price.
People on their knees and they put it all up.
Even the price of the stuff in 2nd hand shops is so ridiculous, that shops are now full to bursting as the people who need to shop in them, can't afford to pay the prices they are wanting.
There is a huge difference between making a profit and taking the piss.