question about these tests

I don't know why I even care since I didn't use nor ever will use these tests.  But I was wondering if you tell them that your u/s showed girl and they had guessed boy and then they do a re-test, then why can't they just say oops you're right we got it wrong the first time, it's a girl.  What is that really doing for you?  Do they still give you a refund or what?

For me two things:

1.) If my re-test comes back girl then I get a refund right away.  If not I have to wait until birth and fax a birth cert. (which is kinda of weird to me) My refund should be about 225 dollars or so, so it is worth it to me.

2.) I want to be counted in their accuracy results.  Which I don't know for sure that they really do, but if I didn't do anything or make it a big deal with them, I probably would not count as the % wrong.

So, I realize I got scammed but I still refuse to just sit back and do nothing, KWIM?  I've learned my lesson.

Thanks for answering.  Now I understand why you would retest.