While rationally you might think so, in practice you tend to act differently than that. Here's the best example:
Let's say that you a running a risk of, for whatever reason, having to pay $1M in any given year with a 1 in 1M probability.
Your expected outcome is -$1 per year, which isn't much. So if someone came and offered for you to pay $1 for year for that risk to go away, you'd be indifferent.
But utility isn't linear. Losing $1 wouldn't make a difference in your life, but having to pay $1M would most likely destroy your life financially, leading to significant hardship.
So the cost, to you, of -$1 isn't the same as [1/1M]*-$1M, the latter is much higher. With that in mind, if someone offered you to pay $1 to get rid of the risk, you'd most likely accept.
In a similar way, let's look at the positive side.
Let's say you're broke, you have $0, and I offer you $10 for 1h of your time. Would you accept? Most likely, yes.
Now imagine you had $1M in the bank. Would you still accept $10 for 1h of your time? Probably not. And if you had $10M in the bank, the odds of you accepting would be even smaller.
That's because marginal utility (of pretty much anything) has diminishing returns. The value of a thing to you is different if you have zero of it, or if you have plenty of it.
The result is that even if you think that rationally the value is all the same, it isn't, and you'll actually be valuing things differently. And there's nothing irrational in that.