In general, we seem to give a lot of credit to “free” stuffs.
This is obviously a mistake in our mind’s processing. Upon a closer examination, what’s important is the difference between the benefit and the price, not just the price:
Value (x) = Benefit (x) – Price (x).
Getting a free rotten tomato is not going to be valuable.
Paying 25$ to buy a book that boosts our morale or inspires us to think is indeed valuable.
No, it’s invaluable.
Free things usually cost us more in the end. Mostly because their benefits are negative. And sometimes because their actual price is > 0, which means it’s practically a loan, not a purchase.
Similarly, being cheap in terms of price is not what really matters, logically speaking. Value is.