Why shouldn't it apply in this case?
Because it's unconstitutional. (Which I already said.)
Do you know how legal formulas work?
You mean like the quadratic precedence? Sure.
1) Person uses profanity, rude or indecent behaviour or loud noise near building used for religious purposes with intention of causing disturbance and without good reason.
AND
2) He does that within house of worship itself, or close enough to it to disrupt the service held within.
Close, but you missed it.
1) disturbing a house of worship if such person intentionally and unreasonably disturbs a building used for religious purposes
AND
2a) engage in such behavior within the house of worship
OR
2b) engage in such behavior so close to the building that the services are disturbed.
OR
2c) A person injures, intimidates, or interferes with any person exercising the right to religious freedom or who is seeking access to a house of worship.
Mind you, 1) can be said to occur by anyone even remotely close to any church regardless of what they're doing, so other than clarifying 2a - 2c, it's not relevant.
It doesn't have to. It's legal formulas, not english grammar contest.
Grammar established meaning. In this case, it establishes that the modifying clause only applies to the portion that would be grammatically correct. Either interpretation would be equally correct otherwise. It provides us a way to distinguish between the two options. Further, it is supported by the first sentence.
Will this definition of disturbance help to clarify the matter?
Sure. The "disturbance" applies to the building. That is wholly consistent with the defintiion of the word. If outside the building, then the service must be disturbed.
Ergo, not only can it be used to regulate religions that worship, it also discriminates between religions that worship and those that do not. Further, it is discriminating based on religion and not objective universal standards (such as noise violations). Therefore... it's unconstitutional.