Here's my two cents.
If you're going to make the argument that the deal is always out there, I'm going to flat out tell you that you are wrong. Some of the members live in very affluent, upscale towns and cities. Places LEGO either sells strong or sells out. To say you just have to drive around harder is ignorance.
I have gotten some insane deals, and I mean insane. 60 percent or more off is an easy thing to hit here come clearance time. I work hard at it, yes. I hit every Walmart, Target and Kmart within 45 minutes of me roughly every week or two. I like the thrill of finding an epic haul. Sometimes I'm at my 24hr Walmarts at 1 or 2 in the morning.
But don't confuse things. My hard work only pays off because I live in a poor area of the U.S., one of THE poorest actually, and most people down here who are struggling to make gas, food, or rent money can't afford the high MSRPs of LEGO. So, they sit on the shelf until they have to move in the next line, and in comes the clearance deals. If I tried to replicate this back home in Atlanta, I can assure you my success wouldn't be anywhere near what I'm used to, even with more effort put in on my part.
The fact is, some people will get lucky, some will get more out if they put more work in, but the true deciding factor determining your LEGO profitability aside from working captial is going to be the place, and thus the market, you live in.