Moisture will remain in the leather, and when its constantly moist it isn't as strong and will eventually start to rot, and your shoe will die. If you're in a job where you actually need dress shoes, you probably can afford another pair.
Although it is not ideal to wear the same pair of shoes more than one day in a row, your situation is a little bit different. To be honest though, you should probably think about investing in another pair--if one pair will last you 6 months, two pairs will last you 2 years, etc. Of course there are diminishing returns once you have a dozen or so, but if you have that many shoes longevity is the least of your issues
I do intend to get a second pair once i find out what i want and once i start getting paid (just started, and we get paid once per month). living in a fairly wet climate probably doesn't help with the moisture issue either... maybe i should look into something with a rubber sole next.