That would be a big turn-off from going back to the store. Like others have said, there is a time and place for things, and I don't think a store in front of mixed company is appropriate for stripping down to underwear and walking around. And the whole staff helping one person and not being able to help (or even offer to help) would make me think twice about going back. Have you considered writing the store about your experience?
And you make a good point Jules. I was an art school model for a time in college and part of my job was posing nude (note - there was no touching of ANY kind allowed, and if there had been I would have been out in a skinny minute). Personally, I have no problems not wearing clothes at certain times. However, I feel like I have to think of other's comfort sometimes over my own. Which is why I won't go walking around my parents house in my birthday suit or wear really short shorts and bikini top to go shopping. Or anytime in the winter. It's simply not appropriate.