OP, I wonder what you'd do in my situation. I'm allergic to disposables. Maybe you think you'd just put up with that.
I also have a health condition that (among other things) gives me five-week periods. All the time. There isn't a cure for my condition, not even in 2013, and it can be hard to stop the excessive periods without using drugs that give me unpleasant side effects. That makes the allergy a lot harder to put up with.
My health condition also makes me more prone to recurrent infections and thrush during my period. All five weeks of them. Maybe you think you'd just use tampons instead. Or even a mooncup. If you're that open-minded.
Because of scar tissue caused by my condition and repeat surgeries, I can't use tampons or mooncups. They cause me pain. What would you do then? Shoot yourself?
Actually, as you've probably guessed, I use cloth pads. I started using them out of necessity, but I've been completely converted, because - for me - they outperform disposables in every respect. THey really do make that time of the month (or that 70% of the year) easier for me - less pain, less hassle, greater comfort, greater protection. The washing isn't a big deal, yes, even five weeks' worth - I don't have to do extra loads above my normal. I'm not grossed out by it because I spend my life dealing with blood, and if it bothered me, I'd probably be deeply depressed by now. So I use cloth pads, because I love the change they've made in my life. Because I'm worth it 
.
It would be so easy for me to start up an AIBU thread with a load of offensive generalisations about women who use disposables. I could even end it with 'I know it's an individual's choice, I get that. But AIBU to be just astounded by that choice?'
What I don't ever do, though, is judge other women for any choices they make to make things easier for themselves during their periods, whether that's using disposables or dancing naked in the garden. I do, however, judge you for lack of compassion, lack of empathy, lack of good manners and general ignorance when you start a thread like this. Yes, ignorance, because it should still occur to you that there might be many reasons why people make a different choice to yours, even if you haven't experienced them. The same goes for all the people who leap on the bandwagon. It's 2013, yes, and using washable sanitary protection isn't what we should be beyond. But we should be beyond starting pointing-and-laughing-type threads at the silly people who don't know it's 2013 and don't know they're being gross. We should be beyond acting with unkindness, bad manners, all these things. If you're just after a reaction then you're probably lapping this up, but I'm saying it anyway for the sake of the 'OMG GROSS!' people who maybe haven't thought it through.
For the people who asked questions about teenagers, if you're worried about friends laughing at school, they don't need to know and they won't be able to tell. They don't smell, and I find them easy to change when I'm out and about, even for a whole day when my period's heavy. I do everything wearing them that I did wearing disposables, and some things that I didn't.
Cloth pads work very well for some people and less well for others. It's worth buying one to try it out. Sorry for the mammoth post.