Why do our English teachers insist we say “Bobby and I” instead of “me and Bobby”? Is it because the former does not roll off the tongue as nicely as the latter? Is it because the second one is grammatically correct? Is it because one makes you rich and famous while the other makes you sick and smelly? No.
There are two reasons we are told to use “X and I” instead of “me and X” and neither have to do with linguistics. First, they tell us to say it like that because they themselves were told to say it like that and they never bothered to ask why. This goes back all the way to the people who originated the phrases and is also a disturbing and dangerous trend that is very common; people are worse than sheep, they accept what they are told and pass it on whether it is right or not.
The other reason is in fact a result of the same problem as the first reason. It is because we are told not to be pompous. We are told to be modest and humble and to put others first. This is just a linguistic extension to the self-sacrifice complex that people are so obsessed with. The people who come up with these rules that subtly promote putting others before oneself do so because they expect that it will eventually pay off for them when dealing with others who end up following these rules.
The real question is do they use these rules religiously themselves.