Are all?

• Are all politicians corrupt?
• Are all pro athletes on steroids?
• Are all journalists biased?
• Are all soldiers war-mongers?
• Are all lawyers unethical?
• Are all CEO's pragmatists?
• Are all Christians hypocrites?

When people disgrace their profession, rebuke them, not their profession or what it stands for. Don't dismiss theism because some "professing believers" aren't living their faith.