I seem to collect shoes wherever I go. It's not a disease, it's a necessity. Surely there's no such thing as having only one pair of shoes that's perfectly suited for every occasion in life?
To me "functional shoes" = shoes that are designed to serve a particular purpose. To this extent, all my functional shoes have travelled the world with me.
Here are some examples:

a pair of sturdy walking boots to tackle muddy fields (walking in Auckland, NZ)
a pair of slinky heels to match my eyeshadows (indoors in England)
a pair of sneakers to walk around Taj Mahal (on a trip to India)
a pair of ballet shoes (standing on a parchland in Kenya)
a pair of shoes with chunky heels (attending a wedding in Bali)
See what I mean? There's always a time and a place for every shoes! :) Rest assured I have a pair of ankle length boots to wear with jeans, a pair of comfy espadrille to walk around town, a pair of sensible black shoes (not sure what they are for, yet), a pair of knee-length boots to wear with my dresses, plus some more. Oh, alright, I confess: plus many, many, many, many more pairs... (blushing)
Most of my shoes are in the storage place as I'm sort of "in-between country" at the moment, staying at PIL's place. I do have my favourites with me. I'm an organist by trade, so I always carry a pair of modified jazz shoes with me to play the organ. See whether you can spot my tiny organ shoes on the picture below.
Can't really see the shoes, I know... at least you can see me in action! :)
Back to more shoes. Amongst my summer acquisition is a pair of satin Monsoon shoes, RRP £65, acquired for the sum of £1. I couldn't believe it when I saw the price tag. I asked the sales assistant whether there was something wrong with it. She said, "Nope. Only because it's the last pair left-over from last season." Huh?! Last season or not, I fell in love with them straight away. The next picture shows the Monsoon shoes from different angles. Bear in mind that I do not use them for organ playing, the spiky heels make them almost useless for playing the pedals properly. They're just there for a show, in real life they're worn before and after playing the organ. Such is the life of an organist...