Damn... I could probably write a post that looks more like a book for this thread. First and foremost, I couldn't disagree more that a person shouldn't make a hobby their job or career, or however you want to put it, if they can make enough money to be happy. If I woke up tomorrow and had to show up somewhere and be told what to do, I'd contemplate a bullet to the head.
As for my reply to this post, the reason most coin shop workers are older was answered in the first reply - the experience. You might know a ton about coins, the only probably is there's a million tons to know, and when you do it for a living/job mistakes cost you money. As for opening an actual coin shop that is just pure insanity in this day and age, because you have the Internet, which doesn't stop you from do physical deals in your neighborhood. You'd have to go on the Internet anyway so that might as well be the place you start, and just consider it a home business. (for both net and in-person deals) If you have a spare room make that your coin shop... it works for me, and has for the last 10 years. There's also no reason to wait, because the real experience you have to gain is on your own and no coin shop is going to hire you unless they need someone to handle the register, or sweep the floor. Again, there's a heck of a lot you have to know before you can feel very confident in doing deals. So start now, just buy a little and sell a little and see how it goes. The coin business in general is doing just fine and that's evident by the amount of competition that is out there, because you do have to work for money most of the time.
I think it would be a huge mistake to abandon an education for the dream of being in the coin business because the rate of failure would be much to high. If you work for someone you make no money, and if you do it on your own you definitely need one of two things... a ton of knowledge to make good deals fast, or a ton of cash. Some of both can work quite well but if the next guy knows more you are not going to come out the winner. I have a pretty good handle on quite a few of the types of things I sell, but am not an expert, but do find myself competing with those that are, once in a while. Generally the way it goes is that if you beat them, there's no money to be made, you just be happy to break even. It's definitely all about the experience and knowledge, but you do need money to make money, and I tell you, you can tie up one pile of cash fast when it comes to decent coins. So I would say do the coins thing on the side and figure out a career path that makes more sense.... and only reverse that if you can prove to yourself that you can make enough money at the coin business. It's great to follow your dreams but dumb not to have a solid back up plan. I also question how much interest the younger generations will have in coins and that might also be another risk when putting all your eggs in one basket.
I enjoy buying and selling every bit as much as detecting and the great thing is I can do it 24/7/365! The one issue you will run into is having to leave the collecting behind because it's very hard to do both.
