Who could afford a higher annual deductible who couldn't afford a higher monthly payment?
Your title question, Who could afford a higher premium who couldn't afford a higher monthly payment?, contrasts premium with monthly payment, but those are the same thing.  In the body of your question, you list monthly payment and deductible, which is entirely different. The deductible is paid only if you need that much medical care in any one year.  Most years a person in good health pays little because of the deductible.  Thus, the higher deductible options offer catastrophic health insurance without giving much in the way of reimbursement for regular medical expenses. Note - the original question has been edited since.