The Other Side of the Mountain is Always Green
For anyone, three factors decide the career options available to them, irrespective of whether those options are good, bad, or ugly. Just because the IT sector salaries are good doesn't mean everyone fits in. I have seen many, many people ruin their careers by opting for the IT line when they weren't suitable for it in the first place.
Factors Influencing Career Choices
Coming to the factors, they are [not my words, but those of psychologists in the USA]: Capability, Aptitude, and Attitude.
Since you have not mentioned your educational background, saying anything about the 'Capability' aspect in your case would be a misnomer. One can't get into Sales and Marketing (S&M) without the basic qualifications for that line. Remember, not everyone is Bill Gates, who founded Microsoft without a degree.
As far as the 'Aptitude' (or in other words, interest) aspect goes, you do seem to have it, but I am afraid the reasons seem to be wrong.
Regarding 'Attitude,' at least going by your value judgment that there are no politics involved and such things in the S&M line, I don't think it fits the bill.
If you think the S&M guys can drive any company alone without any support mechanisms like HR, Production, QA, Finance, etc., forget it. I know of many companies that went down the tube just because the Sales guys were not supported well to fulfill the commitments given. The Sales guys had to take the flak from clients, for no fault of theirs, which does seem to be one of the very reasons that you wish to get into S&M. If you have any feeling of 'that's not my problem,' I guess you have a far more serious attitude issue that needs correction. If you don't have any such feeling, that's quite good, since you would be able to see your situation from a 360-degree perspective. Forget about feeling bad for not being able to implement it in your company for now; focus on yourself first.
Frankly, I see a tendency of 'running away from problems' in you. No hard feelings, please. Anywhere, you will have problems. For all you know, being in HR today is nothing but an opportunity for you to learn handling issues/problems. Just give this a thought.
All the best.
Regards,
TS