LogFAQs > #969905689

Consider:
Each new edition that comes out, and people move to the other edition, or, your army doesn't exist.
Each person needs to spend hundreds of dollars, not just one person buying one book.
You still need terrain
An army isn't just that small bundle

40k costs thousands of dollars to play, let alone the time investment for painting.

Compared to:
Buying maybe $10 of dice
One book (if you don't want to find alternative methods for the book)
Maybe a book every 3 months (if you don't find alternative methods for the book)