Pharmacy and medicine are totally different. Yes, they are both health related and are centred round helping patients through the administration of medicines, but the major distinction is that Pharmacy is all about applying the science of medicines, whereas medicine is a lot more practical. As a pharmacist, you tend to use your head, whether its through recalling knowledge of the latest clinical trials to influence prescribing protocols, or through simply recalling some functional group chemistry to be in the position to advise a patient whether or not a new medicine is any "stronger" than an old one. Even the mundane act of dispensing is using science, where you have to dredge more facts from your head, e.g. when deciding whether or not this medicine is OK for a patient that you recall were put on anti-diabetic medicines last year or who you recall had liver problems. Medicine, however, is far more procedure orientated, where medicines are only a small part of it, e.g. surgery, diagnostic techniques. Nursing, again, is even more practical, where they are trained to carry out nursing procedures which make up the act of caring for patients. For this reason, those that want a health profession but want something "clean" that doesnt involve anything messy may opt to do pharmacy, or similarly, those that prefer to practice health care in a more theoretical or cerebral, rather than practical way, may prefer pharmacy. Although of course, the boundaries are getting more and more blurred, with nurses prescribing and pharmacists giving flu jabs.
I mentioned in another thread a while ago how the Pharmacy as a backup for Medicine thing came about. When I applied for Pharmacy some 16 years ago the average offer was BBB to BCC, depending upon where you applied. For medicine, it tended to be around the BBB level, though exceptional candidates might have been given lower offers. This, of course, has been subject to grade inflation over the years. The great backup degree in those days was actually dentistry, where the average offer was BCC. The crucial driving force for the apparant switch round was the opening up of all these new schools of pharmacy, where the number has doubled in the last few years. This has made the course less competative and lead to a drop in the offers.
As far as responsibility goes, I'm afraid that all the health professions are in the same boat. A pharmacist that fails to detect a prescribing error made by a medic will take the rap legally. A dispensing error can kill someone and at present, although there is a campaign to change the law, a pharmacist failing to pick up a dispensing error, even if it doesnt harm the patient , unlike any other health professional making a mistake, can be sent to jail. Pharmacists in hospital also have to do on calls, although I concede that in the grand scheme of things, pharmacy is more conducive to family life later on. I hope that no pharmacy student ever feels like a failure, as its a great profession and a degree that includes a huge range of disciplines and is highly demanding intellectually. Hope this clears things up!