Well, you know, I don't know a whole lot about cooking roasts, much less selecting them. If, then, I were to drive over to Hy-Vee right now and walk up to the butcher counter and ask for a beef roast, I would rely on the presumably qualified butcher to help me select a proper cut of meat.
It sounds more like that you have a misanthropic view of customers, and you suck at providing the "service" part of "customer service."
The title of the thread is "this customer needs a brain," not "God, why do these people keep talking to me?!"
Then try this, "I've never cooked a roast before, what is the best kind of roast?" That will start an easy, pleasant, conversation on helping you.
Rather than just saying, "I need a roast."
And, again, taking us through the painful, long, Q&A process to figure out what you want or need. If you want to have a conversation about what you want or need then try being conversational instead of giving half answers.
You can't tell me in your time as a bartender you never got frustrarted when people kept saying, "I need a drink."
And, for the record, I've gotten numerous customer praise and comment-cards on my customer service and only one, maybe two, complaints from customers even the managers agreed were out of line.
So, take that for what it is worth, I guess.