Speaking in general and in your opinion, do non-believers hold a double standard when it comes to religion?
Such as for example: Demanding religious claims be backed by hard evidence, but then not holding the same standards for their own claims.
Some do. Many humans, both believers and non-believers, have double standards or display some measure of hypocrisy. Others try to guard against it and may hold to a more consistent standard. I suppose it can be said for any group of people.
If I'm just talking with someone, whether it's in real life or in online forums such as this one, I won't necessarily hold to any hard-and-fast rules about the need for hard evidence just because someone makes a claim. If someone wants to philosophize or discuss their various speculations and conjectures, then why not go along and see where it goes?
Where I would draw the line and demand hard evidence is if it goes beyond just idle conversation. For example, if someone is asking for my money or to do something I may not want to do. Likewise if someone makes a proposal to change or enact a law, or if they want to accuse someone of a crime, they should have some sort of factual support or hard evidence to back up what they say.