How does "have to" function in this sentence?

Usually, I think "have to" indicates obligation, which is pretty similar to "must". But today I found this sentence and its usage of "have to" confused me: (it is from NYTimes.com)

Long-term forecasts seem to me rather like time capsules, designed more to provide retrospective amusement for those who eventually have to read them, than to be taken seriously as they are first uttered.

It would be uncomfortable to interpret have to as must since we are not "compelled to read them".

Can anybody explain this for me?

And yet this kind of "have to" is similar to being compelled to read them. Apparently this reading is unpleasant; that is why "have to" is used.

Whenever you are doing something you do not like, it is assumed that you "have to" to do it: why else would you be doing it? This "compelling" may not be literal: a long-term goal may be compelling; there may be compellings reasons or arguments, etc. based on which you feel you "have to" do something. Compare this example, with the even stronger word "to force":

Once it dawned on me that the author had been using the word "compelling" in a very unusual way, I was forced to reread the whole paragraph, because it seemed nonsense the first time I read it.

Here the word "forced" is used in the same, non-literal way: I was not actually forced by brute force, but rather "incited, moved" to reread it, by my desire to understand the paragraph.