look at it this way, the Holy Spirit is supposed to enter those when they accept Christ. the Holy Spirit is supposed to be able to do anything right? So if it wants to use us to speak in another language can it? Because if it can't you are saying the Trinity is not all-powerful if you believe in the Father, Son, and Holy Spirit.
Listen I do agree with you that most people fake speaking in tongues. I agree it is extremely rare and really not necessary since the Bible is translated in almost every language of the world. But the fact is God can do ANYTHING HE WANTS even allow someone to authentically speak in tongues. I don't think He does it that often, but the fact is if we believe God is All Powerful He not only can, but does when he feels like it.