Kind of unusual - I would expect to see the 175/65-14 tires on the base model Corollas - most of the LE and S trims levels come with the slightly larger tire, 185/65-14.
There is not a huge difference between the two - both sizes are supported by the car. The 185 is slightly wider than the 175 tire, treadwise. Overall size, the 185 is also slightly larger in height, but not enough to through the OEM speedometer off an appreciable amount.
You might be able to find a wider selection of tires in the 185/65-14 size though, so that might influence the choosen tire size. Try some online retailers for initial research - www.tirerack.com is one that I've used - good tire information there.