The only time I did Fiddler we very purposely used NO TAPE, NO MAGNETS,
etc...
We bought a LOT of the same bottles, and coated the insides of them with a layer of black latex paint. Thus if the bottles are dropped they break less, with fewer shards. Easier cleanup and safer.
We used REAL hats with NO real modifications.
They dinted the hats with the
bottle in like is traditionally done with the
bottle dance. At the end of the dance they put their hands forward, and nodded their heads down, a finale to the dance whereas they dump the bottles in their hands and catch them.
They practised and practised the dance, and yes they broke a few bottles...
Not a single
bottle broke during a performance, and only two fell during a performance, however the dancer caught it. The dancer who lost his
bottle went "oohaah" and stood aside as if it was planned to happen anyways...
The director really liked the reality of the
bottle dance shown off... No tricks, just a group of highschool students (none actually dancers) who learnt the dance, and practised it to perfection. Everyone loved it!
Personally I think it was FANTASTIC, why do any tricks? Why TAPE them to the hats? Why attach them?
However it does take practice, and there is a small
element of risk.
We had one of the actors in character come out with a dustpan and broom to sweep up any broken glass (as if it were a joke written right into the script). So if one DID break, it would be a non-issue.