Or maybe "nobody" just have studied another line than the book ? But in Blitz as it seems you are playing it is always good if you can get out of the book as fast as possible. Try playing some longer time controls and you will probably see more "book play".
do you study chess openings?

A book like Discovering Chess Openings by GM John Emms (2006)
https://web.archive.org/web/20140627114655/http://www.chesscafe.com/text/hansen91.pdf
will give one a start on understanding what to think about when one doesn't have a memorized move to play.

3 min Blitz 0-1600 - it's rare to find someone who plays opening by book. Even if they do it does not matter, because his overall skills are very low but they are fast. Most play Queen gambit or Kings gambit - very unsound.
3 min Blitz >1600 You start to see some memorized book moves but rarely the understand their intention, but you might get in serious trouble out of opening.
3 min Blitz >1900 players are experienced and strong enough to know their system and not to make some random stupid moves or fel in trap like 1.d4 e5 dxe5 Nc6 Nf3 Qd7 Bf4 Qb4+ Qd2 Qxb2 Qc3 Bb4!
I would say i reached 1700-1800 in couple years in 3 min blitz simply by tactics and general opening principles.
After opening study - really intense - lots of opening and choosing system i hit 2100+ beating even title players - took me 1 year.
If you want real blitz chess play in 3+2 pool - there even 1600 players wil get you trouble if you play like you play in 3 min or 5 min pool.

I wouldn't bother posting in this old man's topics lol.
But you did anyway ?
An admirable self sacrifice in an attempt to save others, and deny a painfully obvious troll its food.
And sure I made a PSA, but I wouldn't ever post a serious reply to the OP.
Man! Now you are doing it again!
because nobody plays the move or what is in the book