There is a huge growth in the number of people in this country who are not claiming any particular religion. This is a very good thing. In a country founded on secular ideas, it is good to have a large portion of the population who are secular in their private lives.
The problem is that a growing trend among this group is to consider themselves "agnostic". In general, the claim is that there is not sufficient evidence to prove that any certain deity exists, nor is there sufficient evidence to disprove any and all deities. This is what is known as a "false dichotomy". In layman's terms, "fucktard logic".
To begin with, there are not 2 potential options, prove or disprove. When someone presents a claim, you can take any position you want, but the default is to not believe what they say until they present evidence. If you are satisfied, you can accept the claim, or you can pursue your own evidence, or you can present a counter claim, etc. etc. At no point is it your job to disprove their claim, although you could present counter evidence if you like.
Even if those were the only 2 options, it would then be ridiculous to believe that you could opt out of the whole process by saying the jury is still out. That doesn't mean you're not in either camp. In fact, if you say there is no decision yet, that means you don't believe them, and you're probably going to continue acting as though you'd never heard that claim.
The misunderstanding can be illustrated quite easily through analogy. The misconception is that this is like two people are trying to convince you to go to one restaurant or another, and you just haven't decided yet. The reality is that one person is trying to convince you not to go out to eat, which is what you have been doing, and 9374329407234893 other people are trying to get you to come to their restaurant.
So why do people take this position? Mostly because being "atheist" has a negative social connotation. It was also historically defined as meaning that you knew that there were no gods, which makes no sense given the etymology of the word. That probably didn't really help. Also, some people just don't like to take strong positions on anything, so that they can feel superior to those who are "extreme" as understanding increases. But I don't know that for sure. Jury's still out.