Chess is a game of perfect information. Chess players at this level do not intentionally play suboptimal moves hoping to trick their opponents. They try to find the best move given the position on the board.
In some cases two moves may be roughly objectively equal, one leading to more complex positions than the other. In these cases players do sometimes choose according to the situation on the clock, their style, or their mood. For instance, if I have more time left than my opponent, I may choose the more complicated continuation, and vice versa. This sort of practical savvy is important, but not nearly as important as many casual players assume.
True, I was thinking more of the latter example. Several equally-optimal options are at hand - most people would pick the one they are most familiar with. A more devious player might pick the option that the opponent has least likely considered, taking advantage of their unpreparedness.
In some cases two moves may be roughly objectively equal, one leading to more complex positions than the other. In these cases players do sometimes choose according to the situation on the clock, their style, or their mood. For instance, if I have more time left than my opponent, I may choose the more complicated continuation, and vice versa. This sort of practical savvy is important, but not nearly as important as many casual players assume.