I don't like giving fake numbers......the result is innocent people (busy people, elderly, bedridden, etc.) being bothered by calls. IMO giving a fake number is cowardly, and giving a fake email is almost as bad.
Actually, the result is not just that, but the rejection that the recipient of the fake number encounters. That is, if I offer to trade numbers with someone and they say they'd rather not, I can dig that. And they're right in front of me, being honest with me. I get the picture, right then, right there, and can maybe read their emotions.
But if I'm given a wrong number, then days later I find it out, and I wonder, did they do it on purpose? If so, was it to be cruel? Did they think it was funny? Do they realize how it'll feel for me when I realize the number they wrote down for me is actually a taxi company?
Are they careless, thoughtless, or just mean?
In college, I got a call one night from a guy who said we'd met a few days earlier. I said not possible, I hadn't given out my number, and he insisted I had, at a frat party. I had to tell him that, no, it wasn't me--I'd never been to a frat party, and I didn't look like he described. You could hear
how crushed he was over the phone. Someone had not only lied to him and given him false hope, but they'd involved me
in it, too--my number and
my name! (I never did find out who; half the campus had my number because I typed papers.) I felt so bad for him.
Don't give out fake numbers. Dodge it, say you're not comfortable yet, or say "I'll take yours, but I'll get back to you," but don't give out fake numbers. Own what you do.