Would it be pretty easy to setup a Roku account that doesn't have a CC number on file? That will most likely be the deal breaker with any person who wants me to setup a Roku for them. They absolutely don't want to give out their CC number to a company they aren't familiar with, but would love to use their product. That's elderly people for you.
I strongly resent that you categorize people of age so negatively. Age is not the determining factor for stupidity. Stupidity comes in all ages and from my experience the gift of stupidity is bestowed upon the majority of people at the age of majority or maybe earlier.
Walmart, because of its attempt to market to the masses, tends to attract the stupid factor. This means we will see more objections to things like a CC requirement. But we will not, I believe, see any greater percentage of objections to that than we do now. However we will see more objections simply because of increased sales.
My concern is that this could encourage an increase of negative reviews and negative word of mouth with more people being too stupid to pre-qualify themselves for Roku or being unable to understand the setup instructions.
There are many other negative issues involved in selling through a merchant like Walmart and just a few positive. It is hoped that the increased sales offsets the negatives but I believe that the negatives will outway the positives in the long run.
I see many many calls to tech support and many many posts for help here with the issue not being resolved coming. And that will result in expenses that will hurt the bottom line. But I do not think it will hurt enough to make Roku really squirm.