Can Google know the IP address that created a Web 2.0 site?

Can Google know the IP address that created a Web 2.0 site?

Some people say that when building Web 2.0's you shouldn't use the same IP for creating all of them because that is a footprint and can lead to the search engines penalizing that Web 2.0 or something. But as far as I have always been aware, web 2.0's don't show the IP address of the person that created it. Just like they don't show you what the email address is of the person that created it either.

If your IP address was published on them somehow then I'd get why you wouldn't want that. But there is no way that Google can even tell anyway right?

So why is it that people think that about web 2.0 sites? Is there some special access key that Google has with them where they can see this data? Would they even want to?

Does it even matter anyway?

I mean, is it because they mean if you're creating lots of them using some kind of bh tool or app that was creating accounts on hundreds of web 2.0 sites like Buddypress, or Elg, Jcow, phpfox, Dolphin sites etc for the purpose of building web 2.0 profile links or something then they can find out and penalize you for that?

As far as I was aware they can't see the IP address that created those profiles on those sites either. This isn't something that I'd do because to me Web 2.0 building is using the top sites only (although those can be good for your tier3's tier4' etc) and it's not something you'd do in one day anyway. Create 1 or 2 a day/week or something and by then you'd have rebooted your PC/laptop 10-100 times and have a new IP address each time anyway if you had a dynamic IP anyway.

So yeah, its probably something that the noobs and blaggers say but that's my thinking on the matter if anyone can confirm that to me?

Thanks!