Watch the two videos:
They both show that the bear has powerful paws to help catching a fish with ease.
If you search for videos "bear catching fish", you will see a salmon swimming upstreams flying into the mouth of a bear waiting there. In comparison, you can see how important it is to do something at the right place and time.
Mecius could have meant that to have the instrument to catch fish is better than to be given the fish.
However, it is important to read the entire chapter before drawing our conclusion. Mencius continued to say, "To survive is what I want. To be righteous is also what I want. If I cannot have them both, I will give up survival and choose righteousness. 生我所欲也 義亦我所欲也 二者不可得兼 捨生而取義者也"
For survival, food is essential. It is to be righteous if food is the result of hardwork. If a bear is to choose between being fed with fish but sacrificing his paws, the bear would rather choose to die of starvation.
Giving up survival for righteousness 捨生取義 is what Mencius wanted to teach.