There are, you suspect, a great many bands who know, in their hearts, that their fans don't really love them for their skills and novelty; all they want is a new album that sounds exactly like the last one. However soul-crushing it might be, the sane financial decision is to eschew invention in favour of repetition.
You don't often hear bands admit it, though, so a small bouquet of honesty to Kirk Hammett of Metallica, who effectively nails his fans as painfully conservative:
Same as last time, then, guys? Yep, same as last time.