I'm speaking in general when voicing this. I'm not taking shots at the OP, Americaman. (Frankly, I tend to see this forum like a big bar/smoking lounge where we share stories, not run boycot campaigns; thus, I didn't regard his post as a tirade to strong arm SPC into caving in.)
What I find annoying, both as individual citizen and business owner/worker, is the prevalent attitude of many customers who staunchly believe a business MUST warrarant their complete satisfaction: this has resulted in a conceited and tyrannical disposition on their part: they treat businesses as slaves, not as equal partners in a commercial transaction, which is what they really are. Business owners are expected to be shaking in fear of the customer being disatisfied in the very least, lest they embark on a smear campaign far and wide across the Internet. Thus, we have businesses all to willing to go through the indignity of bending over, giving away freebies, running their operations at a loss, and firing employees who tweeted 'hateful' comments in their off-work hours (guess it's expected employees are slaves too, belonging 24/7 to their employers). Ixnay to that!
Pappymac's observation is my rule of doing business. Actually, mine goes further: "The customer isn't always right: sometimes he's a eejit". I have another rule: "I strive to do my best, but in no way do I guarantee customer satisfaction"; I've seen enough cases of customers feigning displeasure to avoid paying.
I'm always willing to negotiate and find ways to make good on a mistake, but I'm not gonna let the customer make me his bitch. If he threatens to take his business elsewhere I encourage him to do so: by walking away he's doing me a favour.