I scratch my head at some of the stuff posted here. It would not break my heart if every shelter was torn down. I don't need them. However, why does anyone care what someone else does with their tent? If it takes up room that others need, I get the complaint. Why is someone else's method criticized? If it does damage, I get that. A tent in a shelter is a bit odd. But who is it hurting if the space is there? I think it is weird to sleep outside a tent. You won't see me making sarcastic statements about that choice. It is just a choice. There are tons of right ways to do things. The OP is sseeking to not do the wrong thing. Just because suggestions don't line up perfectly with the way someone else does it, that does not make it stupid.
But ya'. Do it if you want, if it is legal where you are. Don't do it at the expense of others. Don't use screws to hold it down. A free standing tent works best and has a footprint not much larger than the sleeping bag. Ignore people that have input that just want to say their way is great and your way is stupid. HYOH. Have fun.