Businesses should welcome registration because people won't just look at it and think "well I could do that myself!" because of the additional hurdle; hurdles that businesses will happily jump through. It'll separate drones more clearly into "toy" grade drones and business grade drones.
The businesses for drones are anywhere that you want equipment (particularly cameras but not necessarily) that previously it was too difficult or expensive to put a person for either due to practicality or safety reasons.
Drones are now reasonably cheap self-stabilising mobile platforms. They won't be going away, they'll just be incorporated into other businesses where appropriate. It's easy to laugh at drone-races and selfie-cams but as drones become more reliable, more efficient and quieter they'll just naturally find use cases.