We have the right to pursue happiness. If that for you is making an obnoxious amount of money, then go for it in an honest manner and peace be with you. No ethics or moral law involved as long as you're being honest and not manipulating or "price gouging". What's price gouging? Demanding people pay more solely because there's a shortage on something that you have that others need for survival- medicine, food, water, maybe safety, security... That's a form of theft and you'll need to get right with God on that.

However anyone trying to ague that Pinball is comparable to medicine, food, water is being silly. Pricing a pinball machine obnoxiously high might be stupid.... or crazy, or wasting everyone's time,... or brilliant! But as long as you're representing it without lying it's definitely not unethical.