"Cash grab", at least in the sense I'm using it, implies that it's not a good product. Every major release is designed with making money in mind. making money is fine. That's capitalism. It keeps food on people's tables. TDK made an assload of money, did so with a character who was already very popular, but managed to garner massive critical acclaim from just about everyone.
Making a BAD product and leaning on prior name recognition alone to bring people in is a different story.
The big comparisons have been Transformers and Man of Steel. Both of those films largely fall into that category that you're attempting to defend, despite some people enjoying the product.