may be a silly question but why is gst paid on strata fees?...

may be a silly question but why is gst paid on strata fees? surely collecting and holding money to collectively pay for the services the strata needs isnt in itself a tax supply?

ie say insurance bill is $5000(including gst) between 5 owners.
each owner gets a bill for $1000 plus gst = $1100 from the strata company. they then pay the 100 gst to the govt and 1000 to pay the bill per person.

if instead we got an email saying your share of the bill is $1000 please pay it directly then we would save $100 on gst??.

what am i missing here? probably to do with the claiming/paying of the gst but i can never seem to work out how this works?????