I am an experienced Catalan player and choose 3.g3 order exactly to disallow
Queen's Indian. Considering my knowledge and practice I can say that most of White players move 3. g3 for the same reasons.
Little more deeper:
Main issue here is that at the point after 1. d4 Nf6 2. c4 e6 White doesn't really know if Black selects some classic structures (like Queen's Indian or Nimzo) or more sharp (Benoni, Benko). By сhoosing early 3. g3 order White limits Black from Queen's Indian, but by this price allows Black to switch for more preferable options in, for example, Benoni: 3. ... c5 4. d5 ed 5. cd d6 (or 5. ... b5!?), where g3, Bg2 system is relatively harmless for Black.
Thus, one shouldn't treat 3. g3 as the move that just narrows down Black's options. It has own drawbacks. I can speculate that if you are preparing as White to more positional-styled opponent or Queen's Indian player it is better to consider 3. g3. If your main weapon against Benoni is the system other than Fianchetto (g3, Bg2) you probably need to check some QI lines and go 3. Nf3, it will be more sound in this case.