True, but it is easy for us on the outside to see that their hope is delusional. But when you are the person hoping that your loved one is miraculously alive in there, you hold onto that hope as long as possible because accepting the fact that your loved one is dead when their body hasn't been found has to be a hell of a hard thing to do.
One week after my mom died I saw a woman with the same hairdo as my mom pulling into the grocery store driving the exact same make model and color car as my mom’s old car. I nearly got myself killed sprint across the parking lot to verify it wasn’t mom. I was at my mom’s bedside when she died, I saw her coffin lowered into the ground, my mom hadn’t been behind the wheel of a car in three years and that particular car was sold to a scrap yard a year ago….but still I had to check. So yeah, if one of my loved ones lived in surfside, I would still be clinging to a sliver of hope that they may be trapped alive in a pocket with enough air to survive.