Travel is a set of unique experiences that form unique memories. Part of what’s addicting and pleasurable is that it helps slow down the perception of the passage of time, among many other positives.
It’s also self reinforcing in that when you think back, you tend to disproportionately remember travel vs other experiences.
There’s clearly a lot more benefits than that, but it certainly seems like a significant factor.
My theory is that it's less that it only stores unique memory, but it is always trying to resolve things into generalizable patterns. Kind of like a compression algorithm - but in this case not always accurate or reversible.
For me, time during the pandemic has been flying by because every day is nearly the same. Wake up work, maybe excercise in the evening, play video games, sleep.