"You'll never win a customer with an argument."
For the topic at hand (Garadget), the rep was absolutely out of line; I don't know if this was a policy they were enforcing or just a bad day, but I've been called worse than that by my customers even on good days, and it should just roll off you at this point.
But, always trying to please the customer has a nasty effect of backfiring a lot of the time, since sometimes pleasing them means getting into support situations that are untenable.
Respect? Absolutely - usually customers are smart, and as long as you are reasonable and respectful, so are they. But aiming to please gets people into a bad mindset of not being able to deliver bad news or establish policy.
Edit: corrected spelling mistake.
The more nuanced formulation acknowledges the existence of limits on what will be done - you don't, for example, get a 90-day delinquency reaged off your account once you pay up to date, no matter how you ask.
It also, and I think this has merit for Tier 1 reps who are constantly exposed to all the marvelous and frequently trying vicissitudes of humanity, explicitly calls out respect as a value. Certainly I found that explicit reminder useful from time to time, and I know others did as well. Perhaps this fellow might have, too.
If you're going to split hairs to that degree I would absolutely expect you to notice that the customer called the product a piece of shit, not the support engineer.
In the course of a year and a few months spent doing credit card Tier 1, taking on average about 150 calls per day, I dealt with a lot of people. A very few of them were indeed just assholes, of the sort who'll open with "your product is a piece of shit" just because that's their attitude in general. They were easy to identify, but hard to work with. A vastly greater number were instead moved to unusually assholish behavior out of frustration with the situation in which they found themselves. Given a touch of professionalism, they were easy to identify, too, and easy to work with as well once given the opportunity to vent some of their ire and settle down enough to behave rationally again.
Perhaps the customer in this case is just an asshole. But my experience, which is not inconsiderable, shows that that is extremely improbable. Given, as I mentioned before, a touch of professionalism on the part of the support engineer, I see no reason to doubt that this situation could have been brought to the same sort of mutually successful outcome which I so often produced in my time wearing a headset all day. Instead, the engineer has succeeded only in producing a PR nightmare for his company, and I hope also in getting himself fired for cause. (I would! On the spot, in a heartbeat. Just as, in any of the several customer-facing roles I've had, such incredible behavior on my part would certainly have incurred the same response.) I fail to see how such an outcome has any utility for anyone involved - the customer's still stuck with the same broken product he started out with, and the company's out both money and reputation, too. I'd be fascinated to see how anyone could argue that that's a reasonable expenditure to buy a mean and fleeting little moment of satisfaction for one support engineer.
This is a useful perspective to take if you're in sales. For a support engineer, not so much. When I did Tier 1 for credit cards, the mantra everywhere invoked was instead:
"The customer is not always right, but is always deserving of respect."
Which has always struck me as a much more balanced and sensible attitude to take, when the objective is to solve a problem.
Sometimes that problem is between the keyboard and the chair. It happens. But it's still a problem that merits solving, rather than being a jackass about, because it's still stopping the customer from using your product, and why should he give you money for something he can't use?
Of course, that doesn't seem likely to apply here - pretty hard for an app crash to be a PEBKAC. I've found it a useful enough perspective to merit mention here, in any case. And perhaps such an attitude would've dissuaded the Garadget representative in this thread from so precipitously making a fool of himself, too.