I've wondered for a long time why teabags come in pairs. 1 Weirdly I've never actually looked in to it until now. One idea I've heard is that when used in a teapot, you will need two tea bags. But that's always seemed a bit odd.
Luckily, Yorkshire Tea2 wrote about this 7 years ago:
So why pairs? Well, think about the shape of a single tea bag – it’s flat at the edges but plumper in the middle, where the tea is. Stack 40 of those on top of each other and you’d get a pretty wobbly pile.
Pair them up, however, and they’re much more stable. It makes them easier for us to work with, and stops them falling all over the place when you open the box.
Makes sense.