It's a 32bit and from an old version. Perhaps they don't want to annoy their paying customers? In this way they get more information from you. I guess it's good for their marketing research. Hopefully they would conclude that it would be better to make the software more freely available.

I'm not sure how big the market is for them or related array language. Seeing J became essentially open source, and kdb+ released their 2nd grade 32bit for non-commercial use too, I guess the industry is shifting toward more consulting/training services.