It's just way too easy to get a patent these days (by one estimate, more than 85 percent of all applications are ultimately approved) and way too difficult to challenge a frivolous one.
The whole point of the patent system is to encourage invention. That's why the government grants a temporary monopoly on original ideas. The problem is that many of the ideas that are awarded patents these days are not original at all. And more often than not, companies apply for patents as a legal defense against litigation rather than to unleash some amazing new product on the world.