Reputation and badges are both meant to describe one action contributing to the community.
Every time you do something which contributes to the community, the system is designed to reward you. (No, it's not perfect.)
First, on the topic of users who ask too many questions.
As has been mentioned over and over. This is a question and answer site. Some users (most users) provide many times more answers than questions. They are generating content by providing answers.
Some users ask many more questions (hundreds in your case.) These users are generating content by providing questions. Even if they never accept a response, the users who answer those questions are still able to gain reputation by providing thoughtful and insightful answers.
So, basically, we never want to punish users for asking questions, because that is what those users have to offer the community. That isn't quite what we are talking about here, but it is a foundation.
The more important part that we are concerned with is the issue of gaining reputation for marking something as an answer. As I prefaced at the very beginning, reputation is designed to positively encourage good behaviour. The badges are all designed that way too.
Community concerns caused the SO team to create the "Acceptance Rate" which is actually a negative tool that is designed to shame people into good behaviour, but that is not the norm. Normally, StackOverflow is designed to help you integrate by rewarding positive behaviours.
Marking an answer as accepted is positive behaviour. You are contributing to the community by selecting the specific answer which solved the issue. Arguably it could be claimed that this contribution is worth more than a mere 2 points. It is the quintessential purpose of the site to have questions and answers. Without marking something as "the" answer, we have questions and a stack of suggestions.
Bottom Line, Marking something as accepted is important, and it is worth incentivizing in general and I have no problem if someone is gaining reputation this way. It is also incredibly difficult to gain that much reputation the way this user has.
This answer of mine has a few links which are also related somewhat.