There really aren't that many rules to learn unless you're in tournament play. Things like touch-move, not castling through check, castling after a king/rook move and correct en passant capture are all irrelevant online since the software won't let you/your opponent make an illegal move. OTB is different of course and I learned when being taught by my father early on, so no, I've never sat down and read them all specifically.
How many of you really read ,and learned,the rulles of chess
Yes, you are right. You tend to know the normal rules, but not the obscure ones unless it affects your game
All the rules affect your game. If you go into a game not fully appreciating the nuance of something like the threefold repition or 50 move rules, or en passant, you're not forarmed with the information you need to make the best decisions throughout the course of the game.
Just because a condition isn't currently present in your position doesn't mean you shouldn't be thinking about when it might be at some point in the future and factor that in to your decision.
I will translate to English some lines from Croatian edition of : Chess Manual by Eduard Piacun ICA from 2011
Some people think that can make their own "view" or simple make some addition or cut-out from official rules but: Any federation has freedom to put more details in rules of the game only if they are not contradictory to FIDE rules in any way.
During the game it is forbidden to use any kind of notes, source of information,advice ,analytics source, electronic device.
If any el.device makes any sound=contumation
They must be turn of, if you keep them in your pocket.
I have witnessed many cases of losing a game if your mobile rings.
I am asking this since I notice many strange questions about what is legal and what not-on and of the board-, playing blitz, rapid,standard or correspondence chess.
If there are FIDE officials here maybe it would help to write a column like "Judges Corner" or something.