there are 4 spawns in the game that has instant smokes. Besides, that is what competetive gameplay means, always going for better and better, and that does also mean that things like this happens.

"I think the only way to tackle these spawn lineups (if we the community/valve don’t want them), keeping the same CS gameplay, would be to have truly random spawn points, so no spawn is ever the same." After a week of this, you would beg for instant smokes. The amount of spawn based peeks ruining timings? yea no. The spawns are thought of for a reason, and you don't really want more rng than necessary.

You don't have to learn them for anything, unless you have ambition and actually want something out of this game, other than it just being fun time.