What about say, $5? Isn't that what people used to say in like 2011 - "Just buy $5 of bitcoin" which is worth like $2000 today or something.
If they are afraid of spending $5 on bitcoin, are they as fearful spending $5 on a cup of coffee? A pack of pencils from the store? It's just $5..
For $5 it's simply not worth it. Fee exceeds value. Moreover, if you buy a cup of coffee in a store, you are not afraid that it will disappear. They are afraid that it is just a scam, so they prefer to get something for free because they don't waste anything except time.
So make it $10 or $20. Both still cheap, people are out here buying games for $60+. But the thing that happens when someone spends money on something, generally, they pay more attention to it, do more research on what to do with it, how it works, etc.
I guess I'm saying air dropping bitcoin works but has pros/cons but also promoting buying bitcoin can work, has its pros/cons.