Interesting question. While I agree that a lot of doctors are arrogant and rude (I am a doctor myself) I would hope that not ALL are. Pulbic perception of physicians has really changed over time. Doctors used to be your friend downt he street who would make house calls and take phone calls at home. Insurance companies and lawyers have changed all of that. It is no longer the lucrative job it used to be. In fact, doctors are among the very few who have their salaries lowering each year rather than rising with inflation. Couple that with increasing malpractice insurance costs, ambulance chasing lawyers, and rising office costs and it puts quite a damper on the profession.
Hopefully those who go into medicine nowadays do it for love of the profession rather than the money. Other answers that speak of doctors becoming "jaded" through difficult training and abuse hold some truth. Medical school and residency are tough. In one study done by the Journal of the American Medical Association, they reported that over 90% of residents (doctors who have completed medical school and are in specialty training) have been verbally abused (defined as yelling or degrading speach in a public area) and over half have been physically abused (defined as a hit or slap at minimum).
The pressure is high. We have a profession where the slightest mistake would lead to harm or a lawsuit. How many times have you been to a restaurant where they got your order wrong? Did you think to get a lawyer and sue them for it? I often think that if I made as many mistakes as I witness on the outside, patients would die.
None of this is meant to excuse poor bedside manner. I think a lot of doctors forget how it feels to be ill and need someone's compassion and help. But, I hope that patients can sometimes understand that we are under a lot of pressure and probably work too hard (I have to see 25 patients a day to pay my mortgage and support my family). If a doctor is rude, don't take it personally. Being nice often is the best way to get good care. Being rude back will often lead to minimal care (doctors are human too!)