What's the social etiquette on sizing down my wife?

So I'm in a welfare state country and I'm finally doing something with my weight as well as my wife. We've both put on a bit of pudge.<br><br>So she's lost 3KG and I'm taking her out to celebrate. She's not sure of her size as they vary between brands, so we're going into some restaurants, she's going to try on some dresses to see how they fit her.<br><br>She goes into the changing room and comes out looking a bit self conscious. I'm assuming it's because she's shy about wearing clothes she's about to buy, so I'm encouraging her to come out and show it off to her husband. She's reluctant, I see the owner of the store come into the changing room and hand her the next size up. I ask my wife's opinion of the dress and she says she loves it but just has to get one size up.<br><br>I go outside to smoke a cigarette and I hear the owner of the store talking to my wife. She's asking if she still loves the dress and she says yes, she's just a bit self conscious about it being too tight in some areas. The owner is like, "It's okay dear, we have sizes for all shapes and sizes. This one will be nice with your body type. You don't need to feel ashamed of yourself. You're very pretty." I'm just thinking, yeah, my wife has always been a bit self conscious. Then the owner is like, "You should consider getting your husband down a size too, you can lose a few pounds." Then my wife looks at me, and I'm like, "No, I'm fine." Then the owner just goes, "Okay" and that was it.<br><br>I was a bit surprised my wife said that. So I'm asking, is that rude? Should I take her out for a walk and lose some pounds of flesh? Or should I just let her live in peace? Should I get her a gym membership? Can someone give me some advice on the etiquette of sizing down your wife?