You have a lot of questions to ask yourself. Why do you want to be a vet? Do you want to be personally responsible (and if it comes to it, liable) for a patient? If it's to help low income areas, how do you intend to do that? Will you be working for a charity or 501c3? How will you keep costs low?
You need to start by taking college level courses. Every vet school has prerequisites you must complete to matriculate into their programs. You need to start by first figuring out which colleges to apply to and then by taking the courses that satisfy their needs. You will likely go into deep debt unless you have a lot of help from home. Not necessarily from undergraduate level courses (some of which can be taken at a community college), but if you do get in to vet school, it costs a lot. I went to an in-state program at one of the cheaper schools and still graduated with 6 figures of debt. You will need to do well in these classes and it may be a challenge if you aren't used to being in school and getting into that mindset.
As for this point, well there's a lot to be said about it. I've worked with and for many vets at this point in my life. I have met exactly 1 that was trying to make more money off of clients. He didn't increase costs of services, he simply added more services than required. So you may have experience with one of these doctors, but they are RARE. You may think that prices are increased in a way that is "unfair" to owners. When I charge $1200-1500 for an exploratory surgery, a lot goes into it. First there are the costs of consumables like suture, fluids, fluid lines, medications, lab reagents and slides, and cleaning materials. Then there are the costs of goods that I must spread out over every surgery to make my money back - that includes things like surgical instruments, radiology, suction, specialized instruments, and furniture (kennels, surgery table, exam tables, etc). THEN I need to pay my overhead which includes things like being able to keep the lights on and being able to pay the rent. Finally, I need to pay my staff. By the time all of this is said and done, I have spent roughly $500-700. The additional cost is because I can't see any other patients during that time and because the clinic has to make a profit. Why? Because if I can't improve the clinic, I won't be able to keep up with other clinics in the area in offering the best care possible - I won't be able to go to CE if I don't make a certain amount of profit each year. I won't be able to pay for a new blood analyzer when I need to. Those kinds of things. Also because this is a business, and people are allowed to charge for services to make money. Veterinarians are severely underpaid for the amount of school we undergo and the amount of debt we accumulate.
When I see low cost clinics in the area, I always check their prices. Often, they are able to offer vaccines at lower prices because the manufacturers give special pricing to 501c3 companies. They often are able to sell them for less than I can buy them for in those cases. This is the same for most equipment and monitoring that they offer. As a non-profit, they simply have more leeway than a private business. You also claim that many people are "rescuing" animals from shelters. I, personally, hate that terminology. People are adopting animals, not rescuing them. They get no privileges from private vets for doing this because people often adopt animals because THEY want them. They do get some privileges from the shelter - usually the pets are as up to date on vaccines as possible and have come spayed/neutered if possible. Often, if they were ill, the illnesses were treated first.
Finally, I must address your behavior in this thread. SDN does not tolerate name calling or insults to other users. Users disagreeing with you does not make them less adult than you. It simply means that they do not agree. Most of the people you have said are less than adult are practicing DVMs with more real world experience than you. That doesn't make your experience invalid, simply naive. It is not an attack on you, it is simply an observation with their experiences. It's easy to make judgements as a vet tech or assistant. It's less easy to make those same judgements when you have personal experience as a veterinarian.