I've noticed many people who wish you not to go with med are hoping to get into med as well, which is expected. I made it into med this year - think me naive but it has been my dream, my goal for the last 10 years or so.
Many of those I know who made it into med, or who were hoping to receive an offer, are almost 100% sure they want to do so, and likely will be willing to put the work in to succeed at any cost. If this isn't what you truly want, but instead cars and girls, I don't believe it is the course for you. Not just university, but being a doctor is a lot more than just being naturally intelligent or lucky in the UMAT, so being misinformed is the last thing you want to be when accepting an offer into Medicine. I highly doubt you'll be getting a whole lot of girls, and money won't come until much, MUCH later. (for money, do dentistry!) Also, as others pointed out, many who did not make it in could be bordering on desperate, and it would be somewhat kind of you to reject and let them have the opportunity they so greatly desire.
In my opinion you should not take it and do something you enjoy, especially if you know you will not enjoy being a doctor. But ultimately it's up to you.
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I think that if you are naturally intelligent then you will grasp concepts more quickly and with greater ease, meaning that you can spend less time trying to do so. If you study hard on top of that, this means you have that remaining time to stamp out mistakes, errors, etc that are needed to succeed in exams. For me, I am not naturally smart but I work my ass off - I spent too long trying to understand Physics concepts (which every naturally intelligent person found boring and too EASY to understand), or couldn't comprehend good english essay structure, which meant less time for actual revision or perfecting exam technique. Luck + exam preparation (knowing the layout, structure of the exam) helped me out on UMAT. Hard work can get you far but most likely will not get you the 99.95.