I do understand the downside of whole disk encryption, but I do it anyway. Mainly because I have been in IT for so long, and have seen the consequences of lost/stolen laptops and the info on them. Even stuff that people don't really bother protecting (temp files, or deleted files) can spell big trouble.
I am lucky though... I am capable to do my own PC support, so other than bug fixes or something extremely esoteric, I am usually doing just hardware issues. If I have to hand a laptop to get repaired, I will copy the data off, erase the drive via TRIM or DBAN, toss a basic OS on there so the techs have something to work with. Then, when the laptop is returned, I'll erase the drive again, reload from an image.
For me, whole disk encryption is the lock on the front door. If the laptop is stolen, with encryption, it is "just" a hardware loss that I had. Without, it is both hardware, and data that has fallen into the wrong hands.
As for a RAM freezing attack, my latest MacBook Pro, it would be fairly hard to do, as the chips are soldered on the motherboard, so I am not really worried about that, or TEMPEST attacks, especially with how relatively low value the data I stash on the laptop is.