I believe, that many of the aspects of most TMA's parallel aspects of many religions. The tenants, principles, virtues, and personal development create room for a spiritual spark. I think that from this aspect, some are drawn to make parallels from their own religions. Albeit that many of these TMA's were originally taught with Asian religious overtones (Buddhism, Confucianism, Taoism, etc.. .), ALL religions strive for a similar 3 goals: 1. resolution of grief over ones past 2. understanding how to live ones life in the present 3. Overcoming FEAR of death. The principles of TMA's lead a person towards an honorable path to deal with #2, which IMHO, is where many people draw this parallel.
I believe this parallel between the principles of TMA and #2 are great, and they may bolster ones faith. However, it is entirely different to draw conclusions of #1 and #3 from martial arts, that is overstepping what TMA is, IMHO.
As stated in previous posts, IF a dojang is upfront about how it conducts itself, I see no problem with a "religous dojang," but it is not my cup of tea. I do, however, touch on the Confucian and Buddhist philosophies that alot of the Moo Duk Kwan tenants and traditions are based on in some of my black belt classes. If my students wish to draw comparisons to their own spiritual path, I believe that is a powerful thing (just not my job).