I completely agree with Sickof.
I've just had to organise a funeral - relatively simple and obviously under COVID restrictions - and thankfully my family member left enough to pay for it herself (just under £5K); but I don't think many really appreciate all of the costs involved. It doesn't help in people's mindsets, because it's not something you actually wanted to buy, of course - and the big bill can come suddenly, rather than having plenty of time to think and plan, like with a wedding; but closing off somebody's life is expensive - just like starting off in life costs a lot, but we're used to the NHS bearing the brunt of that.
A good funeral director (open 24/7, as has already been said) will cover so many big and small tasks - each of which take time and incur costs. Just to take a couple of things for example, something as simple as pallbearing needs four people employed to be there. Also, nobody wants a cheap and/or old car to carry their loved one's coffin - and they cost a fortune to buy and run and replace after not many years or miles - even something like servicing them must have to be done very frequently, as they simply cannot break down during somebody's funeral - and if they're away for servicing a lot, you need more than one of them too.
Don't forget, also, that there are a number of unpleasant but necessary things that have to be done when dealing with a dead body. Funeral directors aren't going to give grieving families all of the gruesome details about what they've had to do with their loved one's body, but they've still had to do them nonetheless.
There are a number of costs which they have to pass straight on to the council, the church etc (the abovementioned £1K out-of-borough charge is disgusting, granted) and, just because we only see the coffin for a very short time, it's a solid, expensive item designed to carry a heavy weight and last (albeit unseen) for a very long time. It's a bit like when it seems garages are ripping us off, when their labour charges are very fair and they've just had to buy in an expensive part to fit on our behalf.
As for it being 'big business', why shouldn't they make a decent profit and earn a good livelihood for doing it, like any other business? There are hardly loads of people clamouring to become FDs - or even to do most of the jobs relating to their loved one's death that would be possible to do themselves.