I don't know MAM, but I always assume these rules exist to stop abuse or a headache rather than some kind of elitism.

Multiple accounts with the same ip? You get into ban evasion and the argument of "ThAt's NoT mE, tHaTs XYZ" if you just ban them all.

I've read reasons about the client thing, but I don't remember any, and the mobile thing, probably just stops an argument about "I'm trying, my phone just keeps killing it". Could it be simpler? Of course, but if you deal with people all the time sometimes it's just easier to make a rule and be done with it.