Jess, I'm so proud of you!! You've become a member only a short time ago, and you are already taking the bull by the horn to try and eliminate some of the problems in your chapter and improve things. A lot of members go through 3 years until they take as much initiative as you have. Good for you!!
As to what you said - yes this has really nothing to do with glasses or anything else - it is DEFINITELY a power struggle between 2 factions of the sorority. Kind of like when your mom and dad would have a fight supposedly over your bedtime or something, and you knew darn well it had everything to do with THEM and nothing to do with YOU.
It sounds like the late-night (relatively speaking) exec board meetings are not helping things at all. That's one of the lovely special issues you face at a commuter campus. If they refuse to change the meeting time, there should definitely be a group email or a yahoo group set up. Things like a house - the whole chapter has to vote on that and be informed of it. It can't just be "oh exec board decided blah blah blah" and they expect everyone to welcome it with open arms. It sounds like a very small faction shoved the alcohol policy through with a lot of members not knowing what it entailed and now people are saying "hey, where did this come from?"
When are your all-chapter meetings? Something better to do might be to have, for example, e board at 6 and the all chapter meeting at 7. That would be a big improvement over your current schedule. I know if I had to go to a meeting at 9:30 PM after a day of classes I'd be so exhausted I wouldn't give a @#$% if we voted to buy an elephant and put a dress on it.
Good luck, and let us know how things go.