Getting frustrated is an emotional response, you don't have to get frustrated.
I've had people snap at me occasionally (not because I was asking for help, more because they were assholes in the course of doing their regular job) and the only thing that happens is I avoided them and kept a written record of the times they'd been unpleasant in case we ever needed to talk to HR.
That being said, I don't think it's an eventuality that people will always get frustrated with other people. I've never had anybody inspire "rage" in me in work situations. Other than some times I was working on tv sets and people were screaming.
Also, it is possible to communicate reality of programming and "right mindset" without loosing control in the process.
Some people find it easy to stay calm and patient, some much harder. And some are able to recognize that "I am pissed now, better not respond immediately". Yet others are able to be polite and nice even while pissed - e.g. have above average good emotional control.