The main problem however is whether public funding of non-essential services is morally justified, which I discuss below.
If that is truly your believe, I do feel much better, that it is not a discrimination towards religious institutions. Yet, I argue forth...
You're missing the point that, we consider it morally wrong for one group of individuals (a government in this case) to forcefully take money from others (taxpayers), under the threat of violence, in order to provide unnecessary luxuries to another group of people.
Does the fact the robbers are in the majority make this situation justified?
When else is taking money from people to fund unnecessary lifestyle choices moral?
Recreation allows the derivation of happiness, joy, pleasure, all of which are neccessary for society to thrive. This I do believe is "neccessary".
Now, it comes to your example of Pornography. I laughed at this example, quite simply because it is such a cheap shot... Pornography is not funded, as society view it as immoral, and so do I.
Now, if the community, or some organisation, was to put forth an event providing free entertainment in the form of a movie, (similar and yet dissimilar to pornography) then the goverment will fund it. I believe this has occured various times?
That being stated, however, all is relative. Who are you to judge what organisations are neccessary or not, for the upholding of society, or morally justified?
I can just equally argue that everyone must pay for their own education, since funding for public schools can be given away to Charities to save lifes across the world. This is morally justified, as life > education?? Now this is not what i am proposing but just continuing on your logic.