Sometimes I do, got in the habit when pg with DD1 as needed more support, then a year of bf so needed feeding bras on at night, then DD2 came along so it all began again. I've just stopped feeding her and its been lovely taking it off at bedtime now, much more comfortable.
I do but only because I'm breastfeeding and if I don't I wake up with milk all over the bed so need something to put the breast pads in! Never did before I had DS. Can't wait for the day I can go to sleep again without one on!
I did once by accident (must have been very tired) and was surprised to discover it in the morning under my vest and to have slept comfortably oblivious! I have big massive boobs Nottalotta 'hidden support' is definitely not for big boobs, there's never enough space in there for boobage.
Another person here with rather large norks, my bra comes off as soon as I get in, sometimes I will wear a soft bra whilst relaxing around the house, nothing in bed, just hang free, I find it very comfortable.