2) If you can reduce "why" to measurable quantities, then science will tell you "how". "Why" might be defined as lower crime rates, lower conflicts, better wealth distribution, etc. You know, stuff religion tries to fix but doesn't do that well.
3) Problem is that I hear that from reasonable and unreasonable people alike. It's like hearing "but I am innocent", yeah, well, even the worse criminals say that. With religion, though, what people consider unreasonable can end up being stuff that should be up for logical / practical consideration and yet they are not willing to view it from a logical / practical point of view.