Purely in the interests of science you understand, I have purchased a packet of M&M's and a packet of Smarties for the purpose of comparison. .... The Smarties of course come in a tube, while the M&M's come in a bag.

I don't think I've ever seen Smarties in a tube - just in a box. And, re: different versions of treats: this weekend, I had a Caramilk bar that had been made in South Africa - instead of creamy caramel inside pockets of chocolate, it was a golden-ish-coloured bar of solid pieces, but it somehow managed to taste pretty much the same!