The first (few) time(s) they're fun, yes, but ... as I said ... when you've played something a multitude of times, know the plot inside and out, and are now merely looking for an ultraviolent fix of ultraviolence itself ... they no longer matter — I wouldn't replay any of the Bioshock games with a view to being surprised, for instance, and really wouldn't need (or have any interest in) the details ... I'd purely be interested in fun combat in an engaging environment.
And even the first time, unless they advance the plot in some significant manner, the only reasons for seeking out secrets are:
a) weapons
b) ammunition
c) upgrades
d) funds for the above
e) bodycount (100% opponents¹:kills ratio)
___
¹ And/or bystanders ².
² There are no innocents; merely the guilty … and bonus points ³.
³ And if there aren’t … kill them anyway — because you can …
