I'm going to approach this topic differently as if I was a business consultant engaged to advise a privately owned and operated marina (not part of a large group). I would concentrate on two areas. First would be volume, filling as large a percentage of slips and transient spaces as possible and selling as much fuel as possible. Second would be maximizing revenues for those services.
I would survey competition to start. However, giving anything away is something I discourage unless a compelling reason. Look at fast food restaurants that charge for extra ranch dressing over one or two per customer. Look at charging for cups of ice. I remember when I was young and my father had small business clients and he had a pizza customer who would give discounts and free food to friends and every customer seemed to become a friend. The words my father used were "you can never give your product or service away. If you want to give someone the shirt off your back or reach in your pocket and give them money that's fine."
Some of these things are the difference between profit and loss. They're also the funds for maintaining the pumps and the laundry equipment in top order. Not charging for items that you can reasonably charge for is like throwing money away.
We own retail stores and I hate the very concept and idea of "free shipping." It's not free. It costs. Yet, we provide it because Amazon and Walmart and others have forced it. Much like them, we do provide free in the way least costly to us and we do charge for immediate or same day. Amazon claims not to charge for Prime Now same day. How is it free if you pay over $100 a year to belong and then you're expected to tip the delivery person. Now, with Whole Foods, Amazon is giving Prime members "free delivery" through Instacart. Well, you fail to reasonably tip and you'll not be hurting Amazon, you'll be hurting the personal shopper and delivery person who used their time.
I do understand the argument against nickel and diming, but the costs of these services are not nickels or dimes to the marina. Pump out, toilets, showers, laundries, WIFI are all costly to provide in a quality manner. So are things like Security. Yes, including them all in the base service prices would be most convenient, but it also means charging those not requiring the services to cover the cost for those who do. It also is a marketing challenge as customers tend to look at two things when comparison shopping, price per foot and price per gallon.
As a consumer, I hate hotels charging resort fees or charging for internet. However, we the consumers have forced it. We go to Travelocity and look at prices. Two hotels charge $150 and $165 and we like $150 and then when we check in we realize there's a $12 resort fee and $3 internet charge. And they aren't optional.
After this topic arose here, I talked to a large marina operator that recently began charging for pump outs. They did so because they felt they were being taken advantage of. People were skipping pump outs at previous marinas knowing they didn't charge. People were buying 100 gallons of fuel to get a free pump out. They also lost some business when they started charging. They don't yet know if it was a wise decision.
I think the decision is very difficult but while it's $5 here and $10 there for us the consumer, it's part of staying solvent for the marina. There are substantially fewer marinas today than there were 10 years ago. As a customer, I'm going to strongly object to something I consider to be dishonest or some form of fraud or price gouging. Jacking up the price of a compressor after a hurricane or the price of water, I'll report to the state immediately. I don't consider a $5 fee for pump out to be price gouging and I will not object to it. I want pump out availability and I want the equipment working right. Oh, and I will gladly pay for in slip fueling or pump out vs free or lower price, but only up to a point.
There's no right or wrong but the issue is not simple and it's not dishonest or gouging.