There are about 100 projects using Unreal3. So there must be good reasons for that

And your comparison with 3ds max ist not very good. 3ds max is a good software but not the best. All max users I know tell how often it crashes. Plug-ins are often built in quick and dirty.

The movie "300" has been made with Lightwave and Lightwave is much much cheaper than 3ds max.
Sometimes the most expensive software is not always the best.

For pure modelling some other tools like Silo or Modo are better. And ZBrush is the best for creating details. Max ist just a well known but very old tool.

MS Office is expensive. OpenOffice is for free. I wrote many scientific documents with StarOffice / OpenOffice because it is better, better support for formulas, big documents work better and faster, direct vector graphic support in your documents, inbuilt PDF writing and much more.

Max and MS Office might do better marketing and there are simply more warez copies around there. That still does not mean that they are the best.