The second question has been still floating around my brain. It is a really good question and I think deserves a more thoughtful response than what I posted earlier.
My version of the OP question: How do people afford the time/cost of dive trips?
I don't think there are any "right" or "wrong" answers here -- it is all a personal decision.
I suspect much of the answer is going to be unique to the individual. Are you going by yourself? Do you work in the industry? What are your other obligations? What is your income?
That said, if you have an interest:
1) Make it a funding priority. Set aside a bit each month for a future trip. This works for a Galapagos trip in six months or a Roatan trip in four years. Start now -- set a trip date and a savings target that will get you to that target a few months earlier.
2) Look for ways to economize on the trip. Go off season. Use a frequent flyer credit card. Shop for packages/hotels. Be flexible about when and where you go. Use FF miles to go partway or all of the way there. Eat like a local. Bring snacks. Split the costs with others. Stay somewhere safe and clean that is close but not on the water. Stay closer to town and avoid the taxis. In terms of time, work harder part of the year and try to carve out some time in the slower season of your occupation.
3) Have fun. Two weeks in the Galapagos or a weekend charter to the Channel Islands. Or a short drive to the local dive spot. It is all good. The big time is where you are at.
4) Try a trip. My first trip, I was poor and diving was only one element of my trip. That gave me motiviation to dive and plan future trips. That fairly inexpensive six day trip started it all...
5) Imagine a dream trip. But a realistic one (not the over water bungalow at the St. Regis or a hut on Lizard Island). What is it like? Beach? Shore diving? Pool? Swim up bar? Dive camp? Fluffy spa towels? Then, see how much more that trip is than the one you have planned. You might be surprised.
How might this play out in real life? Lets say that it is you and a buddy splitting the costs. You could go to Bonaire and stay at WannaDive hut. Room/Unlimited Air/Truck would be $475 per person. Add departure tax and marine park fee and breakfast and you are around $600 per person. Throw some snacks into your luggage and spend about $15 per day on food. If you could use FF miles to get there, you would be good to go for just about $700 plus gas.
OTOH, you could stay at a regular room at the Carib Inn (about $120/nt including tax) or about $420 pp. Add food, departure tax and marine park and you are probably around $600. Add the truck and you are around $760 -- and can shore dive right off the dock for another $100/wk. So about $860 plus gas plus breakfasts... For me, that $160 plus breakfasts is worth it to be on the water with a pool. For others, it would be a waste -- they would rather save that money.
Or go to CCV in Roatan for about $1200 plus air for a week. That is food, diving (shore and boat), lodging, taxes, etc. So, if you could set aside about $25 a week and work a deal using FF miles, you could do that once a year...
OTOH, Lizard Island is about $5k/week per person. Plus diving -- at very high prices. I would love to go but could never justify that. Not even if my income doubled.