This has been an ongoing issue in the reefing community and believe me I know how you feel , I have even named them "flippers" take a freebie and flip it for a few bucks , it's a shame , truth is that the hobby is expensive and they will defend themselves by saying the following phrases :
1) if you gave it to me , I can do what I want with it!
2) so what's wrong with trying to recoup some of my expenses ??!?
3) and the infamous , they have another flipper friend go on the thread to co-sign for them by saying , I don't see anything wrong with it if you gave it to him , he can eat it if he wants!!! .
Bottom line is that it is an optional obligation for most reefers to do the right thing and spread your growth , again I say most because 90% of my corals came from other good reefers like yourself who gave to a better home or trimmed big colonies so that they can supply other reefers with the hard to find stuff in the effort to stop those who give snazzy names to corals in order to catch other reefers in a ripoff deal , or they give because they feel good about trading and sharing .
I never charge and love to give and help and am anti profit in this hobby , I have even made trades only after receiving the approval of the person who gave me the coral initially ...... It's a bad topic but what I do is I share the names of these people with my other good reefer friends and have a quiet red book that helps me protect fellow reefers from these frag worms.
Sorry for your incident , no good reefer deserves this to happen to them , and by all means inform those close to you , don't use the reefer rating as it is faulty and gives the person the option to bash you in return.