Despite being a Now TV customer, I think that its extremely short sighted of Now TV/Sky not to have a more broader reach of devices for the Now TV app to be on.
Considering that Amazon Prime Video amongst others aren't on any Now TV device is stupid in my opnion. Even though Netflix has finally arrived on Now TV devices, this did in no way make me think hmm I could do with getting a Now TV box/stick.
Personally I prefer the interface of Amazon Fire TV over Roku. That being said I have an LG TV which is where I get my Now TV fix, but I recently purchased a Amazon Fire TV stick for travelling, as the device has apps and app functions that Roku and Now TV do not.
So to hear that there are no plans to add Now TV to Amazon devices is very disappointing.
It is very simple, Amazon Fire apps ARE Android apps, they are written in the same programming language and same file format (APK) so therefore it is almost a "cut and paste" job to do. Customers want choices and if a company tries to force limited choice then we have to look somewhere else that doesn't limit us to the choices that we want to make, how is that good for the company and customer? It results in loss of profits to the company and inconvenience to the customer.