I got called from a cold caller related to a Costco compo I entered, fair enough, I've set myself up this.

But they call me on a Friday an hour before lunch (AKA everyone offloading responsibility before the weekend mode a bank holiday one at that :/ ) and when I explained this and suggested sending an email they just carried on as if it didn't matter.

I don't do well with cold callers. You're already getting my manager tone, but to further disrespect my time rather than asking when would be a good time to call back or using something less invasive seems baffling to me if you want a sale.