I think maybe the OP is from the NE and is used to the rust belt ports that have little activity, closed shops etc. I use to live on Galveston Bay and can attest to the fact that there is constant traffic of huge tankers going through the bay to the ship channel carrying oil imports /grain exports.

Add to the fact that the port crosses the intercoastal waterway, a barge canal that snakes the Texas Coast to the NE and you have quite the traffic.

If someone is interested in Southern Port traffic, look at the Port of Corpus Christi, again I suspect it has more traffic than most NE "big city" ports.