The only reason Vargas seems so disrespectfull in his losses is that he is very emotional. He was so disgusted with losing to De La Hoya, he just took off and left the ring as soon as he was able. The guy wears his emotions on his sleeve and that means that he has a hard time swallowing his pride and congratulating someone who just beat him. He's not happy about losing, and he's not going to play nice and pretend to like it. The De La Hoya loss hurt him bad. I think he had a right to be pissed at Trinidad... and quite frankly, I think he was just very upset at how the fight went in the 2nd Mosley fight.
It's too bad Vargas doesn't have the chin of that other fat guy, James Toney. Mayorga is the perfect guy to take Vargas out. Vargas will go out, fittingly, via KO/TKO loss.