Lululemon are weird. They do anti vanity sizing, but are very stretchy. I got some over ten years ago in Vancouver before they came over here - check out OG me - and whereas I should not be able to wear them as the founder is fatist I still can! i got a thermal half zip running top in the sale a couple of years ago so I can do running in my active wear and it is warm and comfy and has lasted really well. I don’t want anyone to see me in it though ! Sweaty Betty power leggings stay up really well when running - every other kind I’ve tried attempts to escape under the muffin top. So I consider them worth it for public decency.Especially when Lululemon don't own a single factory and their leggings likely have the same provenance as the £30 leggings she looks down her nose at. What's so special about them is they are status signifiers. See Sali's comment: "Bought them in about 90 seconds as a punt" because she was early for her date with Alice du Parcqueque, like it's no big deal to spend that kind of money on a whim.
I did note she failed to mention her size for once. Too far from 0 for her liking?