I put my Graber i3 in the trunk of my car every Wednesday when I took it to the Bay Area Reprap meetings for around two years… the only detriment that it suffered was wear on the main plate where I used it as a handle.
To echo other people’s comments, I’d imagine it depends on the printer. I don’t think my kickstarter Printrbot LC+ have fared as well (plugging/unplugging the PSU, electronics exposed on the bottom, cantilevered Y, etc.)