Cheaper to fly from Knoxville to Phoenix with a layover in Memphis than to Memphis Directly?

I am looking at tickets to go from Knoxville to Memphis but the flights are super expensive roughly $450. However if I book a ticket to go from Knoxville to Phoenix it is only $150 and has a layover in Memphis. If I don't check in any bags and just have a carry on, could I just not board my connecting flight to Phoenix and be okay? I don't have a return flight to Knoxville to be canceled by the airline so no worries there.