Newbie Question: Culture Modifiers

[Purna]

I'm still waiting for UPS to deliver the retail game, so I only know what I've seen in the demo. Perhaps this will all become clear when I get the manual, but I am really curious...

Does the 'culture' setting do more than apply the cultural modifiers to the characteristics as indicated in the table? If not, some of these culture choices make no sense to me.

Why would you choose Xenophobe over Schemer, for example, when Schemer has the same bonus to Intel and no penalties?

Similarly, why choose Neutral over one of the many cultures that only has positive bonuses, like Traders, Artisans, Scientists, Workers, and Schemers?

And why choose Merchant or Engineer, when you can make the same characteristic changes "by hand" on the next screen and get more racial points to distribute (50 for Merchant and 450 for Engineer!)?

I am befuddled.