Adventure fiction - heck, fiction in general - depends on coincidence: people turn up, or fail to turn up, at the appropriate moment; opportunities arise, or fail to arise, at just the time that will drive the protagonist to action; etc.
That's not to say that fiction must be "unrealistic" in the sense of wildly implausible. It is to say that, if you looked at 1,000 human lives, few or even none of them would exhibit the same degree of dramatic "neatness" and development as one finds in fiction. For the same reason, even the lives of people who lived exciting and dramatic lives generally need editing to be rendered dramatically apt (eg for biopic films or historical novels). The editing needed to make real human lives dramatic can be large or can be small, but editing is required.
There are a range of techniques, in the context of RPGs, for managing the editing, the content introduction, etc. The most obvious and (I posit) universal one is that of choosing what events to spend time on in the context of play, and which ones to elide. Do we bother to play out all the time spent looking for the sect members, or do we just cut to the discovery of them? And if the latter, do we mark of "time spent" on a campaign tracker as part of the process, or not? Different systems suggest different answers.
In Classic Traveller, a PC or group of PCs spends a week looking for a patron to hire them to undertake some (typically exciting) mission, they have a 1 in 3 chance of finding such a person. Is that realistic? - We are marking off time on the campaign tracker, after all, and in Traveller that will cost you money for upkeep, berthing costs for your starship and ultimately ageing rolls for your PC. Or is it unrealistic? - I've got a skillset comparable to some of the characters the Traveller PC gen rules can yield, but I don't think if I spent a week hanging out in "bars, taverns, clubs . . . or any other likely places" (to quote from Book 3) that I would have a 1 in 18 chance of being approached by an Arsonist, Cutthroat, Assassin, Hijacker, Smuggler or Terrorist (to pluck the top line from the 6 lines of the random patron table).
In the Star Wars universe, how often are bar patrons maimed or killed in bar fights? We don't know - the inspiration for those scenes in the original movie is the western, not a bureau of statistics report on the incidence of drinking-hole violence. If I sit down to play a Star Wars game and there are none of those western-style tropes, then the game is going to suck.
In the universe of Classic Traveller, it's a given that dubious persons who hang out in "likely places" will be hired by somewhat shadowy, sometimes unlikely, patrons to undertake dubious, shadowy and unlikely tasks. That's what makes the game happen. (Or is at least one way the game happens. The other is to play a trading game. But that variant also rests on tropes that weren't conceived of via statistical analysis.)
If I was playing a game which features sect members and teahouses (or cultists and inns) then personally I would expect that from time to time a visit to the teahouse will result in a meeting with sect members. Different systems and different moods will affect how much we care about time spent waiting for sect members to show up, money spent bribing hospitality staff for tip-offs, etc - but that doesn't change the underlying expectation.
