I've never ridden with a trailer, but would love to try.

My main reason for not even considering it is the logistics of flying, trains or busses. Not an issue for all of course.

I even find myself carrying my loaded bike on paths that can't be ridden (down cliff paths to get to an isolated cove for the night for example), over fences and road barriers (usually after I've got lost), or over other terrain (swampy ground, through forests, sandy beaches etc) that I imagine would be much much harder with a trailer...

OTOH I have a nagging feeling that most people don't get themselves into as many messes as I do!