We had young campers near us at a local state park... they showed up with a drum set and electric guitars (I am assuming small battery powered amps). The drum set was muffled in some way, and the amps were not too loud at all. They played for a couple hours... and it was great! They stopped at quiet time.
So Yes, bring your guitar!
One of my favorite memories of live playing was not really quiet... wife and I were camping with a large group of firefighters and nurses. One of the medics was a bagpiper - he showed up as it got dark (seemingly whenever firefighters get together, a bagpiper shows up), and played 3 or 4 songs. Now, bagpipes can be heard for seemingly miles. They are NOT quiet! But... a good player, in the right situation, is amazing. Seems like most of the campground migrated over to listen. When he stopped (again, before quiet time), everyone erupted in applause. It was one of those times that you will always remember.