I've had several. Back in the 60s they were very common as were side zippers on skirts. I had a fitted strapless sundress with a full skirt years ago that zipped up the back. Loved that dress! Hard to get into if you didn't have help. It was nice to have someone pull the zipper up for you.
Also had a really cool black sheath dress made of wool with a beaded cowl neck. You know a girl could find herself sitting with her bra and slip exposed in the heat of the moment when the back zipper was slid down and she let the front slide off.
