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Actual decency...? It isn't surprising that decency is coming from you, but rather that it exists at all in this universe. *slightly lifts jade colored glasses*
Having seen multiple girls' point(s) of view on this. It's an odd hand but here's one good way to play it. Honor, Layers vs. Binary, Networking. Reputation.
Honor: Basically what you're proposing. You be honest with them, but not cruel. Basically, it won't work out "like that," but the person actually can be someone to talk to and hang with without being in a "relationship." At some point, no one has to (or can) match with everyone. They just need one person. This means they won't match with a lot of other people "that way." You didn't do anything too far and didn't lead people on. Good on you.
Layer vs. Binary: In line with the above, friends or acquaintances. Different levels and types of activities/chilling. It can be more or less distant depending upon the individual involved. It could be the whole facebook friends deal, or slightly more involved, chill text, or hanging out in a larger group activity (game night, some other club etc). Of course, if they go off the deep end, then there's an obvious answer for that too.
Networking: In line with the first two points, you might not match with her.... but she has friends she talks to.... At some point, one of her other friends might match down the road. Might be 6 months to a year and a half, but you can meet some really cool girl that way. If she is still "friends" and it didn't blow up, then believe it or not referrals happen. I actually set up a girl with a really awesome guy this way; in their case they got married and have two kids. Not always the result, but yeah.
Reputation: Works both ways for all parties. That's one thing where I actually got this idea from a girl I was friends with. This guy was breaking up with her and he actually said he would totally tell any of his guy friends she was awesome to hang with and great. As that girl's friend, I was totally expecting her to cry on my shoulder about how he was a jackass who broke up with her and broke her heart. Only question being the degree to which he did it. To my surprise, he was awesome and she actually ended up dating one of his friends about 5 months later.
You are valid and it is kinda odd to deal with. Your points about changing scenes are totally true. Oddly, people end up dealing with a population who are older but not necessarily wiser with the weight of their mistakes and misfortunes. You're smart to think it through. Hang in there man.
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