Wrestling fans are so fickle. If the booking isn't exactly how you want it, you're ready to bail on it.
Someone earlier said there could be legit reasons for them not having Bryan win the Rumble. For example, he's not fully ready for that kind of program. The point is, we don't know the reason and all we can do is speculate. Would I have preferred to see Bryan win it, Hell yes I would have. Am I going to cry and go home over it, no. Seriously, If I did that every time the wrestler I was pulling for lost, I'd have stopped watching decades ago.
Also, even before Bryan left with his injury, there were plenty of rumors running around that Reigns was going to win the Rumble. This is something that's been in the works for a long time. Besides, if last year taught us anything, we really should never count Bryan out. Or, have you all forgotten how they ended up handling Batista winning the Rumble when everyone was begging for Bryan to win it?