Some of the congregation tithe 10% of income, or more, to the church, not just the fiver in the plate. I mind the Stornoway Gazette published a list of churches and their income when I lived there, the one at Back came out top, sure it was something daft like £8,000 a month.
Radio 4 did a piece last week on churches and the lead, they cant get insured now as 9 a night are being hit.