Well, thank you for asking. There are a number of reasons.
1) If and only if Red Hat thinks SoftMaker Office is a mature, stable, quality product... should they consider buying it.
2) Only if they are willing to dedicate resources over a long period of time to ensure further development as Sun has with OpenOffice.org... but with Red Hat's nature to lead as a FOSS company with better licenses (GPL2 or 3)
3) Only if Red Hat wants to expand its software portfolio with the addition of an office suite
4) Only if Red Hat is willing to switch to it and eat their own dog food
5) Only if SoftMaker Office is independent enough where they can buy the whole thing and not have to redo pieces licensed from third parties (a big if)
Then and only then would it be worth doing. OpenOffice.org seems to have a number of issues... some due to Sun's leadership and methods... and I'm not sure the split with Go OO is a solution... given the fact that it is Novell spearheading Go OO and they have a number of open wounds with the Linux community... regardless of what the apologists say.
Red Hat has a fabulous reputation walking the FOSS walk... and I don't think anyone else is in a position to make it happen. There isn't much competition to OpenOffice.org... and I don't see additional forks being the answer.
I don't use office suite applications much myself so I must admit I'm not sure SoftMaker Office is worth it or not... but they are fairly inexpensive, offer fantastic academic discounts, and offer a try before you buy trail... are multi-platform... blah, blah, blah... so it shouldn't be hard to evaluate. It is worth looking at.
If you are asking how Red Hat would make money from it. How are they making money from other FOSS products? Apply the same logic.