In the past, there were only a very small number of RC's. Now, there are thousands and thousands of quadcopters/etc... that are being sold. They are easier to fly, and people are giving them to their young children for Christmas presents. Personally, I live within 5 miles of a class Bravo airport (my house is actually just under to the glideslope intercept for a runway at that airport (fortunately, it is only seldom used and is quiet). In the park across from my house, there are kids there at least once a week flying these things far beyond sight. I talked to them, but they said that their parents said that it was ok, and they really didn't care. I reported them via the online form on the FAA website several times, and nothing was done. I then called the tower and talked to a supervisor. The police were called and the kids (and their parents) were told that it was illegal and that the FAA would be in contact with them. I don't know how it ended, but I know that they don't fly there anymore.
It is just a matter of time before people are killed by these things.