Maybe there were no jam jars available?Perhaps. The hand grenades in the wine glass thing seems odd. Would a hand grenade fit inside a wine glass? Would a wine glass be strong enough to restrain the firing mechanism of a grenade? Would a helicopter pilot take the risk of finding out by loading up a pile of them and taking them aboard his aircraft?
More experienced operatives than me can say whether such a method of low-rent aerial bombardment would work.
Obvs. not to use a champagne coupe