Why do leaseholders have to pay whatever dreamed-up insurance cost is presented by the landlord? I can show that the insurance bill is too high, so I am not paying and I am prepared to argue my case in tribunal.
The short answer is, because leaseholders are absurdly disempowered and are simply tenants under the law. The insurance contract is placed by the landlord. Leaseholders, who are not party to the contract and cannot find out what the true cost of the insurance is, just pay up. Worse, all decisions about insurance – such as whether to pursue a claim – are made by the landlord, who interests are not aligned with those of the leaseholders.
Again, our advice is to pay it all and then fight in tribunal, with a forensic case. This Times journalist did withhold payment: he had no idea of the risks he was running and he was very lucky: https://www.leaseholdknowledge.com/times-journalist-defeats-mb-freeholds-and-rmg-over-insurance-dispute