It's interesting that zynga mostly gets a free pass from name-calling when they ripoff game ideas. The only way to explain it is that zynga is a public company that makes lots of money, which surprisingly gives them some sort of immunity.

How does Zynga get a free pass? People rip into them all the time for stealing, copying, ripping off, etc. other people's games, ideas, and mechanics.

There have even been lawsuits, some of which Zynga lost.

They make so much money they don't care, and they made that money long before they were public.