It's all those little things, those micro moments, micro seconds, micro bottles, that really matter in life. ;-P That's why you should repackage what you can.
Case in point
On the left, I have a bottle of REI's travel sized sunblock. I bought this years ago and have refilled it for my backpacking trips. It weighs 2.2 oz (for a bottle half full) and even that amount is plenty to last me a few trips. Way to go Liz!
But wait, what's that on the right weighing only 0.6oz?
It's sunblock, repackaged into a tiny container with just what I need plus extra. In fact, it was more than I needed! The awesome thing about repackaging the sunblock was that it's more likely to fit inside the waist belt pocket of your pack (assuming you have one), which means you're more likely to apply it at the frequency you need.
Let's look at another example.
I reused an old micro bottle of hand sanitizer and squirted some castille soap in there to use as toothpaste and anything else I'd need soap for (there isn't much). As small as this bottle is, it was overkill for the amount I needed. I only use 1-2 drops of soap as my toothpaste to avoid over-sudsing. Next time I'll use an even tinier dropper. Can't wait.
Next time you get a tiny bottle, consider saving it and reusing it to repackage for the trail. Doing this will give you such an appreciation for how little we need, and of course, a lighter pack.