As a hardware store owner, I disagree with the true independents being gone. You have over 15,000 independent hardware stores who are members of groups like Ace, True Value, and Do It Best. These are not franchises. They share some branding but that has allowed them to compete and to remain because they share buying power. There are still incredible small town, local hardware stores. You do not get the same feel in every store of either of the three brands even though many of the same products, but only so many brands of chain saw or paint. The few non branded independents are also largely buying through buying groups now as well. Let's not overlook Tractor Supply, Northern Tools or Harbor Freight either.
Here is where marinas differ. There aren't as many as there are hardware stores. Also, you're not seeing buying groups or anything like that but you're seeing ownership. It's more like Sears years ago and Walmart more recently eliminating a lot of small businesses that can't compete. I do believe you'll see large groups like Safe Harbor continue. This is somewhat like what happened decades ago to the independent gas station. Now, some of the independent marinas can survive as owner operated businesses. The problem is when they're ready to sell. There was a lousy market for marinas and still is if you're looking to sell to other individuals. Just not many looking to buy and no one looking to finance a purchase. So one by one they'll sell to large marina groups.
The fact is that selling small businesses is extremely difficult. We've bought many that the owner simply wanted to retire and couldn't find a buyer until us. Marina owners face that. Their kids often don't want to work 16 hour days seven days a week during season. The marina paid for college for the two kids and now one is a lawyer and one a teacher and one still lives in the area and one far away.
Groups like Safe Harbor are the best and worst that can happen. The small independent operator number will go down. However, quality marinas will be salvaged. That does mean ultimately higher rates though.