Like any right minded human, I detest animal cruelty but if you ever watch daytime TV (during this rather warmish spell where working outside is uncomfortable to say the least) you may have come accross programs that show what the NSPCA have to contend with in UK.  All societies and cultures have good and bad members.  As for "educating these people", I wouldn't have thought that was part of our remit.
I think there are laws to cover most bad practices in Spain but the policing of them does appear to leave a bit to be desired sometimes.
I think we might have to put bullfighting into a seperate catagory in this case, perhaps simialar to foxhunting, hare coursing, pitbull and cockfighting etc.
Having said all that, it would be good if we finally find out exactly who has been poisoning the dogs so that the blame can be placed in the right area.