usopp got himself disgraced beause of his stubbornness of his usefulness as a crewmember and the fact he actually thought he'd be able to beat luffy in a 1 on 1 fight, especially since he was heavily injured from the franky family. The crew did not abandon him, usopp left on his own accord and the crew had to accept his choice. Sanji stopped him from healing him because sanji knew if chopper treated him he knew usopp would be embarrasses of having the "loser" taken pity on by the victor's team and that he knew what would happen demanding a duel and needed to accept the outcome of the fight regardless. Zoro didn't bully the crew, he gave them a firm standing that usopp cannot come back unless he sees where he went wrong and give a sincere appology to luffy his own way. It was also to help Usopp learn to take responsibility for his actions and grow up over the fact the life of a pirate is not a childs game, its life or death. Usopp didn't accept that and was still lying to himself unable to see the truth till he saw the crew sail away and finally stepped up and appologized. Zoro also did it to let usopp learn to become the "brave warrior of the sea" his own way by stepping up to the plate and man up. losing kaya's freindship is never gonna happen, if anything, she'll understand once he explains, they are close. his bounty was understandable, plus sogeking IS his name in a way