High deductible – can’t I get a break on costs if I’m paying in cash?

Without insurance, I’d pay less for an office visit if I simply paid cash and told my doctor I was uninsured.  But if I’m in a ‘preferred provider network’ then why can’t I get a break if I pay in cash at the time of service?  If I’m paying in full, there’s no administrative costs that go into collecting the payment.  Couldn’t I get a discount for that amount?