Yes probably worth around melt, they look like bag marks. This is one that could grade AU58 on a bad day and MS61 on a good day. However, I wouldn't ever send it for grading, not worth the fee. Marks take down the grade yes, depending on the severity, the depth, the size, the amount etc. It also depends on the remaining lustre amongst other things. Wear is the main thing to look at for grading a coin, but sometimes coins have weak strikes and look worn and actually are not. If there are quite a lot of deep marks then it can be graded a 'details' coin which is not a straight grade and takes considerable value away from the coin. Take a look at NGC and Heritage Auctions sold pages for graded examples of
Morgan dollars. They are one of the best coins to learn to grade.