You're playing with words. Lets substitute Arabs for Palestinians. In 1948 some 800000 Jews in various Arab countries were driven out or fled and all Jewish owned property was confiscated. No compensation then or since. So, to answer your question, of how often Palestinians appropriate Jewish land, the answer is once, since there was no more left to seize. All the twisting of words and history will not change that reality. You should get the message.
Palestinian man suffers light wounds from rocks thrown by Jewish men in Jerusalem (Haaretz)
from the article: U.S.: Israel plan to build in East Jerusalem harms peace process