100% untrue in every church I've been a member. All offerings and financial contributions are voluntary. Sure, we keep records, but for tax purposes (we provide a statement to all members so they can deduct the charitable contribution on their income taxes at the end of the year) and for expense budgeting for the coming year (even for churches, electricity, heating fuel, etc. isn't free). If a member wants to get married, hold a funeral, hold another event using our fellowship hall, it's permitted no matter what (if any) funds they have given in the past. Non-members of the church can certainly use the facility as well, but we charge a small fee (and are appropriately taxed on it) to cover our expenses (electricity, water, the custodial staff who has to open the building and clean up after, etc.).
And realistically, member contributions make up way more than 80% of our budget. There are some investments that yield a small amount of interest and some facility usage fees, but over 90% of the "income" our church receives is from voluntary member contributions.
In any church where I've been a member, we have never refused access to any member regardless of their donation status.
I hear people say, "The church is corrupt" and "the church does this" and "the church does that", but my personal experience is quite the opposite.