Well, I have. If a wild animal can get stuck in it a chicken can too.
This is true, and I have had some escapees (mostly light, flighty birds like EEs), but only when they REALLY wanted something that was on the other side of the fence (a wild bird feeder in my case). But my fences are 34-48" high and my chickens stay in 99% of the time. As long as nothing is more interesting than what's inside they don't feel the need to get out. I've never had any dig underneath. I doubt that would be a problem in a temporary pen.
These guys were definitely motivated by things on the other side and it wasn’t temporary so maybe that factored in. They were Barred Rocks and RIRs, so not super light. I’m sure it also depends on how you anchor it. I can’t say I remember how that was done but I do remember the poles being a bit flimsy so the fence wasn’t taut in places.
The poster said "chicks can get through it".
topic is chickens, not chicks...this is what happens when people don't stay on topic
What has happened?
Your OP just said "the girls" - no mention of chickens, chicks or specific ages. It was perfectly reasonable to ask how big your chickens are, and to mention that very young chickens would be able to get through one of the fencing options you were considering, in response to the information you gave.
Then the snow fence should work fine.
