Great post emazers. I think many people here see this as an answer to all of their prayers, without really thinking about everything that goes into making wise purchasing decisions and earning significant money this way.
I'll add that you can make a living at retail picking, however, as I've said in other posts, your scope has to go way beyond LEGO or any other single product.
I own a consulting company so picking is not mine nor my family's main source of money, but my wife picks and sells full-time. She makes way more doing that than most people make at any full-time job.
She has a very broad scope in terms of what she purchases and sells. LEGO represents at the most only about 10% of her monthly sales and profits. In fact, LEGO can be tough because the items are generally bigger and take up more space and are more difficult to ship than many other items that can be sold for significant profit.
Retail picking is very seldom a sexy business. It would be nice if we could buy exclusively things we like but it simply doesn't work that way. For example, I just got an email from my wife telling me that she bought 100 Denorex 12 oz. shampoos for $.89 each. Neither of us use Denorex, but we know that can be flipped for significant profits. This is in addition to the 200 units of Botanical Berry ChapStick she just picked up this weekend and the box full of random retired eye shadows she just picked up. My wife buys a ton of things online as well.
I'm in Chicago tonight and tomorrow on business (and will probably get stuck here). You know those shampoos and lotions they give you in the hotel??? Yep, people buy those. Especially when they're nice ones like in the hotel I'm in tonight!
I travel almost every week, so in the evenings when I'm in a new city I'll often spend my time hitting retail stores and picking things my wife has pointed out to me. The key here is that I have no expenses for fuel or wear and tear because I'm in a rental car that a customer is paying for. I also have no shipping costs to get the things home because the airline I use lets me check two bags free because I fly so much. Watching your expenses in picking is key...wear and tear on your car and fuel can quickly eat into your profits.
There's definitely money to be made out there, and significant amounts of it, but I know no one that does it by just focusing on one type of product. You have to do your research, mind your sums, and get out there and dig around.