Is it ok for them to attack your beliefs on that same basis?
Yes, it's even welcome, although I don't characterize it as attack.
How/why is it "fun" for you? How it is "educational" to you? What "experience" are you gaining from it? If you've really thought about this, you should be able to answer these questions.
You didn't ask me, but I want to respond. Yes, I have thought about it and am quite prepared to give you a good answer.
I've learned the folly of bringing evidence to those that don't use it, and a good way to deal with the request to expose its insincerity. I just tell them where to find answers on the Internet, and if they are actually interested in learning, to bring back what was learned and any questions about it, and we can go from there. Go ahead and guess how many times that has happened? It's caused me to extend my meaning of burden of proof. I have none with somebody unprepared and/or unwilling to track a reasoned argument and to recognize and be convinced by a sound argument. How could I "prove" anything to such a person? I've come to understand that proof is a cooperative process, and that without
I gain significant insights here every few months. Only recently have I come to understand that many if not most people don't know what critical thinking, how it differs from faith-based thinking (I group all unjustified belief together under that heading), or what it's power is - what it can reveal and the usefulness of that. I had always assumed that most people knew what it was and had some respect for it even if they couldn't do it themselves, like they would mathematics, but I have discovered otherwise. I finally understood what, "That's just your opinion" means when it follows a sound argument.
Just in the last month I have come to a clearer understanding of what rebuttal is, how it differs from other forms of dissent.
I have discovered (and some won't like this) that when I ask somebody who says he is on a spiritual journey in search of spiritual truth, that he can never tell me what those truths are or how they benefit him. I'm still exploring that. I find it hard to believe that there is nobody with a good answer to that. Some of these types seem pretty bright, especially the dharmics, and I haven't asked any that question, but I read their words and still don't see answers. What is this phenomenon, I wonder, and why does it appeal to so many?
I find great value in surveying the opinions of posters. It's where I've come to see how emotional the faith-based thinkers become compared to the critical thinkers. It's where I've come to my conclusions about the relative harm or benefit of secular humanism and the religions.
I also get the opportunity to develop and clarify my thoughts by composing responses. Here on RF, I have gotten a much clearer idea of what I mean by truth, knowledge, God, religion, faith, critical thinking, free will, evidence, proof, and the like. I get the opportunity to read the opinions of other critical thinkers, and share mine with them. This is where I've learned to write better, to identify and name logical fallacies, and to form more cogent arguments. I couldn't have written this post ten years ago for a variety of reasons (I did this on another site for eight years before it folded in 2017).
There is nothing else like these types of discussion forums available to me. Only here am I engaged in protracted discussion, sometimes over years, with candid, anonymous posters. This doesn't happen in face-to-face encounters with friends and neighbors, say over dinner. The discussions avoid such topics or brush on them briefly, and they are not candid because they are not anonymous. There are ramifications to being candid with coworkers, family, etc.. You get that emotional reaction there as well, but in those cases, such a reaction has ramifications for me and my wife, so I just don't go there. Here, however, there is no social harm. Theists routinely get their dander up, and I'm sorry that they have such reactions, but I can't control it, it's not a reason to discontinue what I do, and it has no social ramifications.
That's an awful lot of value.
It should be differentiated by the idea being separate from the person asserting it. But few people here or elsewhere are able to recognize that difference. They think that to criticize the idea is to "attack" the person asserting it (especially if it's them).
Many here are able to do that, including me.
What you are describing is the theists primarily. Which skeptics are complaining of being attacked by theists? None. Most write like I do - never complain about being attacked, and never having emotional reactions to the opinions of theists.
It's ok really 
