Complex sentence: As it turned out, members of the co-op felt, on average, that this amount was too small, they wanted to save and build up a larger reserve of coupons, perhaps for the possibility that they wanted to go out several evenings in a row.
Split into simpler sentences: As it turned out, members of the co-op felt, on average, that this amount was too small. They wanted to save and build up a larger reserve of coupons, perhaps for the possibility that they wanted to go out several evenings in a row.