Welcome, and happy posting! :wavey:
As to your question - there's not much I can add to the advice you've already been given. Meditation before class is to help you set aside the concerns and events of the day, so you can concentrate on the training to come. Although you see it that way, there is really nothing weird about it - lots of people meditate, in lots of different settings and situations. I understand your concern, that you might respond inappropriately, but you do become accustomed to the situation quickly and easily, the same way you become accustomed to other situations that may seem odd, unusual, or uncomfortable. I would suggest talking to the instructor, both about your concerns, and for a more in-depth explanation as to the purpose and meaning of meditation, which might help you see it differently, and thus help change your reaction.