What is happening more and more is that in certain countries some isps are curbing their customers use of p2p, and in certain cases they are actually disconnecting users, after a number of warnings. The cases you have heard of may well involve out of court settlements being offered, after a threat of court action.
At the end of the day, if you are going to use Frostwire illegally which Frostwire does not condone or incidentally run a book on
then your conscience and common sense must be your guide. More facts will be found if you visit Slyck.com
who report such things in a fair and sensible manner.