@Brian ********
Yes, and then you show the visa. Sorry, no idea what you want to argue about.
The only visa where an onward ticket is required is a single entry tourist visa. Which at the moment no one is handing out, as most countries fall into visa exempt and you get a 2month free stamp.
So, if "what ever airline you are using" is asking for an onward ticket, when you actually have "a real visa", they are in mistake. And it should be simple to point that out at the airport.