Is there any good reason why they should sell it for $40?
Let's have a new survey. Would you pay?
$20
$30
$40
$50
What do you expect in the Player's Handbook at your chosen price?
This is precisely why they have a $20 Starter Set.Assuming this question wasn't rhetorical or unserious... because a $40 price tag would make it more attractive to buyers who aren't RPG hobbyists already. (Though I suspect the upper limit for most casual/new gamers would really be around $30.)
Well... there's an invisible curve that relates price points (and profit per unit) to the number of purchases - in broad terms, as the price goes up so does the margin but the number of customers goes down (but it's not a 1-to-1 correlation, and sometimes a price increase may even lead to more sales, bizarre as that is). I say it's an "invisible curve" because it only has two known points - if the unit is priced at $0 you get no profit, and if it's priced at $VeryHigh you get no sales and so no profit. Everything between those two points is (largely) a matter of guesswork. (There's a comparison I could give, but it's political, so I won't.)
So, WotC should aim to find the 'sweet spot' where they maximise their profits, allowing for those trade-offs - the point where "margin per unit" x "number of sales" is maximised. That may mean a PHB at $40, or $50, or some other value.
Hasbro probably has among the globe's best retail toy and game economists working for them. The $50 price tag is probably very close to this 'sweet spot'. The polls on this site all suggest people interested in 5e are going to buy it anyway.
This is precisely why they have a $20 Starter Set.
The polls on this site all suggest people interested in 5e are going to buy it anyway.
The polls suggest some, perhaps even most, will buy it anyway. But there have also been plenty of posts expressing sticker shock, and this is a community of D&D fans - those most receptive to buying the game. If even some D&D fans think $50 is too much, what do you think casual fans, or potential new fans, will think?
As best I understand, the 4e red box sold well but purchasers did not make the move to the other Essentials books.whether or not the $20 Starter Set will succeed in attracting fans will depend on whether or not you need the PHB to play - i.e., whether or not the Starter Set is basically a demo. If the PHB is required - as seems very likely, based on Wizards' past behavior - we're back to a price tag that discourages buyers, and thus discourages the growth of the D&D fan base.
As best I understand, the 4e red box sold well but purchasers did not make the move to the other Essentials books.
Given how comparatively cheap the Essentials books were, there is no reason to think that buyers of the D&Dnext starter set will migrate to the PHB whether it is $40 or $50. What puts people of migrating, as best I understand it, is not price but size/complexity.
I assume that WotC will be publishing supplements for the starter set that are more user friendly then the PHB. The most obvious such supplements would be ready-to-play adventures.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.