Of *course* an open alternative to something that Novell charges money for is going to cause some people to utilize it instead of paying Novell money; that's precisely the point here.
So it's pretty disingenuous for anyone to say otherwise, whether Novell's paying them, or not.
The question is: from up here at 50,000 ft, "should" those people be paying?
A common business pattern is that a company provides a service, and charges for it, and the potential audience breaks down three ways:
1) People who need none of the aspects of the service
2) People who need only some of the aspects of the service
3) People who need all of the aspects of the service.
What a process like the one being discussed here does, is to convert people in the second category for reluctant higher-paying customers into people who patronize the competing cheaper/free service, which provides all the aspects they actually *need*, but doesn't charge them for aspects they do not need -- in the case of SuSE it's probably paid support by email and phone calls; in some analogous cases, it might be a bigger seat and free drinks on the airplane, or the ability to rebook your ticket for a different flight, or a pool at the hotel... all of these are examples of where a semi-competitor came in with fewer frills at a lower price point, and stole some business from an established player.
In this case, the situation is *slightly* different, since CentOS is using the code that Red Hat assembled into a distribution, and the SuSE project would work similarly... but that's the price those companies pay: they would not have a product line at all but for the contributions of others under the GPL, and they are, therefore, not permitted to bitch about this, without looking childish. IMHO.