While I get the idea of not giving children stuff I see Disney as a special place and similar to not accepting candy from a stranger but it’s ok on Halloween
Halloween is different. YOU go up to the house with a light on and request candy. You are in control of what houses you approach.
Your child is not approached by a random stranger seeking to stroke their own ego by barging into your vacation to give some random piece of junk like a sticker.
I am going to differ here and say some stranger approaching us with junk would not be "pixie dust" but an intrusion into our vacation. You would be demanding we give you some of our valuable time just to satisfy some need of yours.
There is a huge difference between giving away an extra fast pass you received and can't use or a balloon at the end of a vacation or what tankgirl! does above and actually planning and purchasing some junk just to be able to stop people and give out to children on their vacations. The former is normal, the latter is creepy.
OP, if you happen to approach us, please do not get offended if we say "no thank you and turn and walk away. We are on a family vacation and would prefer not to be stopped to entertain you (general you) and your ego. A vacation to Disney World or Land is Pixie Dust enough for us. We don't need strangers to "enhance" it. The cast members go far above and beyond making a vacation special.
Just my opinion (others may differ) but pixie dust can not be purchased. A smile, letting someone with a dancing child in line in front of you at the bathroom, being polite, those are all real "pixie dust." Not stopping some random child on the street to give them a sticker or some other trinket. Real pixie dust has no benefit to the giver (they don't see the results.) If you have to be part of the pixie dust then it is for your own benefit.
Perhaps since we would prefer not to be approached by some random stranger, we should wear "no soliciting buttons" while on vacation to turn away those soliciting boosts to the egos