It's odd that your daughter is in her last year of middle school and isn't starting or playing much. Generally, not always, but the 'senior' group plays or at least starts but their is competition out there so sometimes even a 'stud' may take her spot.
As far as talking with the coach, there is nothing wrong with that. However, as a youth coach myself for exactly this age and older, I will tell you that nothing frustrates me more then a parent questioning playing time during a practice or after a practice.
There may be some pointers that the coach can reveal as to why it is what it is, maybe the coach sees something you guys don't or in some cases, maybe the coach is just a jerk.
The best thing about what your hub said is that she goes to practice everyday and shows up for every game. That is huge and will go along way. Hopefully, your daughter will continue on in high school as well and as long as she is commited and determined and has fun being a part of the team, her day will come as will her time to shine. Make sure she's prepared!!!!!!!!!!!!!!! Good Luck