Small companies have to struggle to survive. So, these smaller game houses have to be creative and they have to find new/efficient ways of accomplishing their goals. The ones that survive are going to be able to produce quality games.
When the smaller companies get swallowed up by EA, it seems that they are basically told what to make. A sequel to a popular title that was, itself, a sequel. They are given better resources, but that only snuffs out innovation, but their creativity can still shine through. EA puts out many good games. And every so often they put out a great game. But overall, I feel it stagnates the market to have such a monopolistic market share.
There's only so far it should legally be allowed to go.