No one but a few naive individuals have the expectation of every pack paying for itself with any set. However, a $9 loss with every pack stings a lot more than $3 (if you're paying MSRP for non-MM packs). With the higher MSRP I think the pressure should rightly be on WotC to deliver a home run with the value in the set.
I don't really see either of those as set that way to appeal to or exclude any subset of the player base. The $10 price tag serves multiple purposes here. It helps reduces the temptation for the LGS to sell packs for more than MSRP since the return will be smaller, WotC recognizes they left money on the table with the original MM, and it helps to maintain a price floor for the EV of the set. It combined with the limited supply makes sure that even if they were overly enthusiastic with the expanded printing it keeps the prices of certain staples from collapsing too far.