The problem with the approach the FAA has been taking on this issue is that the deciding factor is whether money changes hands. If an activity is safe for a hobbyist to perform, why is it suddenly dangerous and in need of regulation when a professional does it? If anything, commercially operated remote controlled planes/helicopters would be safer in a given situation, as the parent company is going to have real liability insurance, and the insurer is going to have all sorts of maintenance and training requirements.
Because once money changes hands, well, they want to make sure you have SUFFICIENT liability insurance, and that your equipment is well maintained.
A realtor probably only has their malpractice insurance - if they crash into a neighbours house, that insurance may not be sufficient, or even covered. The realtor would just close their business, while the neighbour is stuck suing a bankrupt company (they're all "independent franchises").
So the FAA would like to make sure you accidentally kill someone, they can be adequately taken care of.
The other reason is well, drones are getting REALLY popular. The problem with this is how well qualified are these people flying them? A hobbyist probably knows the rules of t heir hobby and is conscious enough to fly it properly.
Some guy with a rich parent buying their kid a drone flying it into traffic and causing accidents? Imagine all those people who can't figure out where the "any" key is flying those things everywhere.
The other issue is well, what jurisdiction is it when clashes happen? If you're flying a drone taking photos of a house, what's to differentiate it from taking photos of hunters, taking photos of nude people on a beach, taking photos of you in your backyard?
Plus, it's easier to go after people with money and regulate that first. Because they're using it to make money, it's easier to go after them for commercial activity than someone who wants to take a neat photo of their kid in their backyard.
It's really only a matter of time before some idiot with a drone goes and misuses it. The FAA is really trying to warn them to not even try so the activity can progress by those who know what they're doing. Want some crazy legislation? Watch it when a bunch of lawmakers get their panties in a knot. It's what led to the awful legislation that banned scanners from receiving cell-band (800 MHz) signals.
They're getting cheaper, better, and are available to anyone with a credit card. And everyone knows there are lot of rich idiots out there who will ruin it for everyone. Especially since the FAA is still trying to come up with reasonable rules that take into account everyone - pilots, law enforcement, commercial interests, the public, etc. Take an idiot with a drone who crashes it into a busy intersection, and you'll have lawmakers screaming "something must be done" and enacting all sorts of overbroad legislation ahead of the FAA.