I don't think you can say one is necessarily better than the other. Some people may be better at going from zero to something than running a larger, steadier firm. These people are probably better off building and selling. Likewise, some people may be great at profitably running large (or at least more stable) firms, but fail at creating something from nothing.
I'm sure acquisition is much better for many, just not what I go for usually...don't get me wrong, I'm happy to get acquired as well ;). The reason I'm wildly guessing that other cities might show better profitability ratios is simply that they have less expectations from the start of acquisition.
