As a quasi-religious person I do agree that public policy and moral imperatives should have a secular basis. For example, when people look back at this point in history they're going to see a particularly nasty stain in the way that 99% of the human population is responsible for a sort of perpetual holocaust of many other species of animal, all for nothing more than a little gluttonous sensory pleasure. That kind of morality is easily argued on a secular basis for all the substantial harms those lifestyles cause, and the sheer amount of tangible benefits for choosing a better way.
But secular policy is dangerous if it does not also support religious plurality. When one or two belief systems dominate, they invariably oppress smaller groups. Diversity of belief is a natural buffer against that.
That said, a religion does not necessarily need to base its exegesis on interpretation of arbitrarily chosen writings. One of the best things religious groups can do for themselves now days, if they want to adapt to the times and survive into the future, is embrace the scientific method in their own ways. Evolution shows us that the things that aren't willing to change and adapt die.
If you believe that your religion is the only valid one, and that the others need to go away, then you are as bad as an evangelical. Anti-theists are just the hypocritical mirror image of evangelicals.