And soon there will be many more people trying to steal coins from that kind of addresses.
Not many.
There are no more than a dozen people in the whole world who can create and
run such software. Keeping and updating in realtime the database is not simple and cheap task.
You can do a following test: send a small amount ( 0.0010 btc ) to "the most compromissed address"
1JwSSubhmg6iPtRjtyqhUYYH7bZg3Lfy1T sha("correct horse battery staple")
and count the sweep attempts here:
https://bitaps.com/1JwSSubhmg6iPtRjtyqhUYYH7bZg3Lfy1T(this block-explorer shows conflicting transactions)