You have the freedom to get the proper permit. This is a situation that has nothing to do with religion. The only issue here is human bodies and vehicles and their effect on the immediate environment.
With that definition, any group the size of the group in question would have to get a permit. If you had a regular poker game at your house, or a group that got together monthly for a bar-b-que, or for whatever reason, do you really want to have to go get a permit? Isn't that overregulation? Don't our authorities have better things to do than to worry about the parking and permit issues involved with a gathering of friends in your own home?