When faced with a situation like this one, we must consider what the two must be feeling. Hermia did not elope, she would have been forced to marry someone she does not love, become a nun, or be killed.
Someone who is in love with a person does not want to even think about being without their other half. This means the thought of being with another is completely unbearable. To demand someone who is in love to marry someone else causes unfathomable pain to the couple. This is exactly what Lysander and Hermia have to go through.
On top of this demand, Hermia is told that she must marry Demetrius or she must become a nun or be killed. For her own protection and general well being, I think it is right for her and Lysander to have eloped. True love is an unbreakable bond. This means that when faced with a challenge such as this, the only reasonable response is to keep the love and hide away from the things that are trying tear them apart. If they had not done this, they would have not been able to love the ones who they loved and would have been forced to be with someone they did not love. This would have caused unbelievable unhappiness This is why , I believe, it is ok for Lysander and Hermia to have eloped.