Agree with GoodLeave. No reason why the batsmen couldn't have gotten themselves out once they reached their hundreds, if they drop you or you keep missing fielders then just walk passed one if keeper is standing up. Appreciate the batsmen seem to be young so perhaps one of the older guys in the team should have said something to them.
I can see why the fielding team did what they did. Chances are if they batted properly they would have received more abuse, both from spectators and the oppo. I'd have used it as an opportunity to face better bowlers and use it as a net session.