The 'job killers' argument is kinda bullshit. I want to kill jobs - I want to eliminate all labor that can be automated, such that in the ideal perfect future, no human ever has to work; they can spend every moment doing things they enjoy without worry.
But self checkout is not automation. No human work has been eliminated. It is the same exact fucking checkout process, only now the customer does it instead, and the store doesn't pay the cashier. And no they don't pass that savings on to you because of course they don't, they just pocket the difference.