While most hotels or resorts that you'll be staying in on your travels have a complete set of toiletries (in small quantities, of course), there are some that don't provide, like for example backpackers inn, or if you're staying with a relative/friend.
So you have to pack some toiletries. But you don't want them to be too bulky.
Before, I usually buy shampoos & conditioners in sachets and those little Safeguard soaps. Then I discovered something.
Haha. Actually, I recently acquired this habit of hoarding on the toiletry set of hotels and resorts. (Hey, it's not stealing ha, it's part of what we paid.)
And you can refill the containers once it's empty. See how economical! Hehe.