Not every operation with Township Cash requires a confirmation window.
The confirmation window only appears when you tap a button that has a price written on it (like the one used to refresh goods at the market).
If you lack resources for performing certain in-game activities, like producing goods at factories or finishing construction, the game will suggest you spend Township Cash to buy what you need to complete an action. The corresponding window with the Buy button is effectively a Township Cash transaction confirmation window — you won't get a second confirmation.
Please note that if you're using Township Cash to speed up a particular action several times in a row, you will only see the confirmation window the first time. For example, if you want to speed up crop growth on several fields at once, you only need to confirm your intention to spend Township Cash once.