Publishers should be required to sell their digital download licences at the same wholesale cost as the physical copy and then digital stores retail can compete on their margins.
(The real problem is the BS that you "license" the game instead of "buying" it so if the "license" terms are violated then the "license" is revoke. THAT's the bullshit that requires government action.)
Who would "require" this? Only one entity can: the government (at some level). Why in the world does the difference in the price of a computer game between different distribution channels require government price controls?
If you don't like the price then don't buy the damn game. If the price really is too high then they won't sell many and they won't profit. If they sell the games and profit then you're just WRONG that the price is too high. It's just too high for you. You're just farther down the demand curve.
People on the demand curve above where it intersects with the supply curve think it's a bargain and buy. Those at the intersection think it's fairly priced and probably buy. Those below it think it's too expensive and don't buy. That's how markets work, especially with non-essentials.
There are people who think it's worth paying full MSRP of $60 for a game on release day. There are others who won't buy it until it's on sale somewhere someday at $14.99 or even $4.99. Which ones are "right" about the price? Actually, all of them.
If you think that games never go on sale, check here.
Ubisoft is flat out wrong to cancel these keys and they should hit with a Class Action lawsuit, IMO. But there is absolutely NO reason for them to be forced to sell the game at ANY price, let alone at the same price for all distribution channels. They could spend a few million to develop a game and then bury it in a landfill if they want. They have NO OBLIGATION to offer it for sale* ** and you have NO RIGHT to buy it.
* - unless specified in the contract signed with the developers of the game, likely due to a deal based on profits or revenues and not a fixed price.
** - and the fiduciary responsibility to the shareholders to prudently manage and invest the company's (and therefore the shareholders') money.