Really nice question ... I don't think there's a sharp cut-off at the club level where tactics suddenly takes a back-seat.
"Hope Chess" (players not checking to see if they have a good response to all the checks/captures/forcing moves in response to the move they are about to play => hoping they can deal with it aftewards) starts to diminish more and more past 1600 USCF. So am thinking that players at this level don't just rely on the general stupidity of their opponent => Just playing safe without a plan and waiting for the other guy to trip doesn't work so well any more. You have to go after weaknesses or make well-thought-of moves that force concessions in terms of squares or pawn structures. These strategic ideas steer the direction of play for both sides.
I always think of this as two competing waiters in a restaurant trying to stack piles of dishes on each other's trays as they pass each other ... while trying to balance their own tray at the same time :)
Depending on who is more effective, eventually one of them can't balance his tray, the dishes start falling off ... and BAM!!! A mistake is made that can be exploited! In chess terms, this usually turns out to be the same basic tactical opportunities ... though these just happened to occur in a gradual way and not just because a player hung a piece or missed a knight-fork.

Many writers argue that for the majority of low rated games, tactics play the key factor. One or other player will likely make a tactical error, dropping a piece, etc.
My question is: about what level does this stop happening? Where do the gears shift from tactical blundering to strategic blundering in people's experience?
I know, that on some level tactics always plays a role, but I think this analysis is right: for weaker platers there is no point avoiding weak pawn structure when you cannot avoid a knight fork.
In peoples' experience, when does strategy start filling out as a greater component of play? When do tactical errors virtually dry up? What level of opponent should I assume makes almost no tactical errors?
(Note: if you cite ratings, please identify what type they are [USCF, FIDE, Chess.com etc])