Some further thoughts on the matter...
Imaginary incident: One person steps on another one’s foot by mistake - on the bus, let’s say.
The one who has been stepped on protests: Πρόσεχε πού πατάς, χριστιανέ μου!
I guess that an approximate equivalent could be something along the lines of: Will you watch your step, dear!
Looking at the wording kinda matter-of-factly, and from a linguistic perspective (however unqualified I am to do that), there seems to be a certain playfulness: we’re being outspoken about our frustration in a fairly cordial way, still making sure, though, that we… let it out!
Among Greeks, it is not uncommon for this sort of register to also be applicable in more intimate settings, such as the household.
I have no experience of English at this level, but I know for a fact that Swedes, for example (and most of Western Europeans, I'd presume), are less trained in the art of fusing outspokenness and cordiality when expressing frustration: Outspokeness usually equals, well, frustration, plain and simple; cordiality typically equals discretion... The grey-zone in between is less populated (both by speakers, and inevitably, by expressions) than it is in Greek...