Ok, I realize I am shouting into the wind on this one, but it's not as simple a complaint as "a month is too long to wait for new toys".
It's a complaint compounded by multiple factors. Among them:
I think you have some valid points here, but I think you're over simplifying the issue. I'm pretty sure that Hasbro wants to sell as much product as possible. It's not like they're all vacationing somewhere and letting the line die or purposely trying to avoid new product at shelf. The distribution on this line has been screwed up from the beginning because demand was much stronger than supply. I think they've been playing catch up ever since and are just trying to send out whatever they can whenever they can send it.
Most stores in my area have a bunch of older CW sitting on the pegs anyway - it's Legacy that needs to get some new product in. If the show drives kid interest in the line, then we ought to see some of the older figs clearing out for kids. That seems to make more sense than shipping in new stuff that both kids and collectors want only to sell the new stuff and not the old. The show is designed to be a pull strategy not a push strategy...if you do it right, the interest in the show drives older product sales and makes room for orders of new products.
As for the distribution, there's a lot of added complexity here that I'm not sure you're aware of. For starters, Hasbro takes massive orders from big chain stores vs. online merchants. They're not going to sit and pick through each case to make sure everyone get's a fair share of each wave. If Target orders 5,000 cases, then they're going to get the next 5,000 cases. That may contain 3 different waves, but no one's going to hold the order up or ship less to make sure the last 1,000 cases contain a 4th wave that isn't ready yet. Big chains order in massive bulk quantities - it's not like Hasbro is shipping out a few cases here and there piecemeal. They also have to get product from Hasbro to the distribution centers, then from the DCs out to hundreds of retail outlets. It's very possible that big chains have new product sitting in their warehouses, but they're not usually going to get that product out if there are older cases waiting in front of them.
Online retailers order less, so they can clear out supply faster. They can probably also choose to order 'x' cases of each wave - something I imagine the big guys pay less attention to. At the very least, they can better forecast what's going to sell online to minimize the amount of old product they have in the way. Online also has the advantage of shipping from one location. They don't have the added steps of getting product to a store, churning through older product first, getting it out to the sales floor, etc. They get it in, add it to the site, and it's available for order - in many cases you can even pre-order to further reduce the wait.
Given all that, I think it's pretty difficult to offer accurate street dates every time (they are usually pretty close in most cases) and completely unrealistic to think that all retailers are getting the same product within a week or two timeline. The only time that seems to happen is when there is a brand new line coming out and that usually comes along with an official "do not release until..." street date.