It is possible to have factors in one's utility function which limit the expansion.

For example, a utility function might involve "preservation in an untouched state", something similar to what humans do when they declare a chunk of nature to be a protected wilderness.

Or a utility function might contain "observe development and change without influencing it".

And, of course, if we're willing to assume an immutable cast-in-stone utility function, why not assume that there are some immutable constraints which go with it?