I'd rather see an argument instead of two grown men holding hands while they both wait for the video guy to get to the replay. I think they do this to save time in the long run. making the teams run their own review first will stop a lot of meaningless arguments and save having to review every call.
the teams have to be in the loop. you cant let the umps ump the umps.... it's not taking long to figure out not to challenge. people are bored, not unhappy with the rule. screaming, dirt kicking and base tossing is much more entertaining than the manager saying "uh, golling, gee,dang, it's nothing, I'll go sit down again."