Every crime news story usually ends with how all the associates of the detained have also been rounded up (or will be soon) & charged in relation to their part in whatever event - however large or small - that the original hapless goon happens to have been caught up in. Dropping big-time, gun-toting dealers in the soup after you've been caught peddling a couple of yaba to some undercover cop seems to be the norm, too.
Any criminal worth his salt is aware 'grassing' your buddies is wrong & generally frowned upon, particularly by the people you ratted out & now have to spend their days lay next to you in some Thai jail & who will surely be inclined to kick the shit out of you every single day, for quite a long time.
What exactly do the bib do to extract these confessions? Surely a kicking would only be effective if you weren't expecting to be shot or burned alive in a dark, gloomy soi one night as revenge for opening your mouth?