As humans, we are conditioned to look for patterns in life and we gamblers try to make predictions based on what we see, while we are gambling. The reality is that these patterns does not exist, but we like to pretend that they do because it helps us to bring order to the chaos that are gambling.
Some people seem to think that your bet size will increase your chances to win, but that is simply a myth. The reality is that it simply means your payouts will be bigger when you do win.
A lot of my friends believe that it is better to spin the Slots manually, because "Auto spin" are rigged by the casinos... but that is also a myth. A lot of things come into play when a bet is made and it has nothing to do with the "auto bet" feature. (Client Seed / Server Seed & RNG and RTP ...)
Have you pressed the "bet" button, before the reels have stopped.. thinking that it will give you a favorable outcome on your bet? Well, I have news for you... the outcome has been decided in milliseconds after you pressed the button for the bet, the GUI interface happens long after that to display the outcome of the bet to you.
(Go into the developer mode of your browser to see this)
What patterns do you see and how much do you believe in it?
Gambler's Fallacy basically. Our pattern-loving brains making a fool out of us and making us believe that just because a particular outcome hasn't happened in a while, would equate to meaning it would happen soon, which is just wrong and is a fool's way of thinking in my opinion.
As for your friends' being iffy with the auto-spin feature of the slots they play. That's a little stupid too as you put it lmao. If the casino could rig their machines to favor them when a gambler uses auto-spin, what makes them safe from getting ripped off by the casino with the manual spin as well? And for that matter why are they playing in a casino that they do not trust?
As for me, I often fall victim to gambler's fallacy, especially back in the days when I don't know better. I used to gamble a lot on dice and hi-lo, as well as slots, which are very prone to this type of Fallacy. I crank the lever, lose, and say to myself that "since the jackpot's not come this turn, maybe in the next couple of spins I'd get it" only to be disappointed over and over again.