First off, strongly agreed that community matters and is worth investing in.

...you are less instrumentally rational than the average christian.

You may be less something, but rational targeting of effort (both doing something besides converting people, and being strategic at whatever you're doing) utterly swamps quantity of effort here. Being charitable ≠ doing good.

The average christian donates about 10% of their income to the church.

Source, or are you just assuming people do what they're supposed to? This (first search result) says the mean is 2.9%. (I would also bet that most Christians don't know what they nominally should give.) (ETA: I read your comment after you deleted the paragraph acknowledging this.)

the christians are investing a lot of resources into their mission of converting the whole world to christianity

I feel obligated to point out (outgroup homogeneity bias, etc.) that far from all Christians see this as their goal.