Lockers are an essential component in public transport. Thanks to lockers, even miserable car-less sickos can do several errands in town at once, like do some shopping, store it all in a locker, and then go catch a movie or whatever.
Cars, one easily forgets, are not just practical for getting from one place to another, they're great for keeping, well, stuff in. What are you going to do with those 100 beer bottles left on you lawn after your party, the ones you're going to recycle after work? Well, you keep them in your trunk. For a car-less person this kind of situation can be a nightmare.
To be frank, when it comes to bottles and cans I just drop them off in an area with lots of drug addicts. (In this town, you can recycle cans and bottles in any shop and get a bit of money. Great stuff, provided you arrive in town after the shops open, which I often don't.) I could drag bags of empty bottles to work so I could recycle them later, but come on...
I use lockers mostly to store clothes and shoes. Normally I keep my city clothes at work, but sometimes I have neither the time, nor the inclination to walk those ten blocks from the station to the office, past swarms of Moldovian and Nigerian prostitutes and shady Chinese curio shops. So I change clothes and brush up in the train's rest room, dump my woodland kit in a locker, and go ahead and do whatever I'm supposed to do in town.
Without those lockers I would be pretty screwed. Still, due to fear of terrorism, they're being fazed out here and there.
Osama is actually screwing up my almost entirely fossil fuel-free lifestyle.