I know it's normal practice, but it shouldn't be.
My house insurance renewal came through, it's gone up almost 25% from last year.
I spent 10 mins on the internet and saved £100. I didn't even go for the cheapest, a reputable company which gets good ratings and which I've used before and been satisfied with.
I phoned to cancel the renewal and they offered to match the other price. I didn't actually tell them to stick it, I was far more polite, but I did say if they can't offer me a fair price first time, I don't want to do business with them, which I realise probably rules out most insurance companies.
Why do insurance companies do this? If the increase had been 5% or less, I'd have probably just renewed. It must be easier for them to retain business than to gain new business?