Possible Bug in Solo Queue

I just played a game in soloQ. My team was Lv 14 - Lv 16, and I was Lv17. We played a soloQ team that had one person at Lv19, and the rest were at Lv22 - Lv23.

I have seen teams balanced with one or two Lv30s with one or two Lv7 players, as well.

I think there might be an issue with the player selection process in soloQ. Am I tripping, or are those things I described not supposed to be happening in that game type?