New and brilliant ideas are much more difficult to gain traction. Great execution on a "cloned" idea is much easier. How many Groupon clones are there? How many of them are making a lot of money? (Hint, a lot). How much money is spent on Pokemon and related collectible card games? (Hint, also a lot).
The point is Groupon Clones did something Groupon wasn't doing (targeting countries Groupon wasn't targeting) meaning Groupon isn't entitled to be the market leader and the other startups are free to create one for their country.
Pokemon is not making a social web game, this is a big difference to the Groupon situation in my opinion as they are different things. I wouldn't say it's a copy just the story/theme is inspired by Pokemon.
Meaningful is in the eye of the beholder.