This is because you intuitively see the advantage of having a bitcoin transaction consume fewer resources (bytes) in the blockchain, but are not yet convinced that scanning private keys will allow bitcoin to take fewer resources (neurons) in the brains of those non-developers who would consider adopting it.
Bitcoin could take "be your own bank" to a whole new level if the vision were more widespread. Bitcoin can let the common man replace the ATM, which for the public, would be a huge way to fire their bank.
It is simple: rather than withdrawing cash from an ATM, you withdraw cash from your computer and print it. You take it to the store and spend it. Spending happens when they scan the cash to validate the key and make the money theirs. You get back your change when they capture only part of a bill's balance and give it back, or they print you a new bill with your change. If you are concerned the merchant or the clerk might later steal your change, you tear an unused bill in half and give them only the bitcoin address and ask for your change to go there. Screw the banks, be your own ATM, and never pay an ATM fee to a bank ever again.
The part I have bolded compresses the concept of "Bitcoin - be your own bank" best into the fewest layman-neuron-bytes. If we want Bitcoin to exceed beyond the domain of people with technical brilliance, then we should not brush aside some of the most practical applications that would make sense to the public because it doesn't sit well with the cryptographic unorthodoxy of human eyes ever seeing a private key.