The one that Giles and the Potentials captured had had his tongue "ripped out" (ironic that it was Ripper who made that statement), but that doesn't mean that all of the others were tongue-less. Back in Season 3, when the First Evil was trying to push Angel into committing suicide, I seem to remember Buffy finding a group of Bringers sitting around a fire, chanting. Maybe Giles just happened to lasso the one Bringer who had been punished for suggesting that Buffy really loved Angel rather than Spike.