I agree with luckynumber8! Go on holiday!
Honestly, I live in Ireland and am a mucky gardener who is perfectly comfortably off and older, and I don't have Dubarrys yet! They're far too expensive! She could easily have got perfectly functional warm boots at decathlon or similar. She is hopping about in her cashmere and silk and dubarrys and you are insulating her - both physically and metaphorically - from the uncomfortableness of her situation.
The poster above who says you equate luxury gifts with love and they equate them with monetary value / convenience is spot on. Gosh that sounds quite harsh. I do think that you are just trying to be a lovely, nurturing supportive mum who wants all her girls to be safe and secure and comfortable. Unfortunately they (he, but also they) are taking advantage of your model of parenting to meet the needs of their own model of living.
BTW there are a lot of American Christian-influenced homeschooling homesteaders who are very against debt and into thrifting and leaving and cleaving (ie when you're a married unit, that's your priority) and the man being the head of the household etc and wife being a keeper at home etc. They all youtube/instagram/podcast it all, keeping cows and bees and chickens and growing veg etc - there are millions of followers. A lot of what you are saying they are doing falls into this category - do you think they are influenced by this type of thing? Just because if so they will be getting a lot of moral solidarity from it, it's a huge movement at the moment.
Have a look at Farmhouse on Boone, Now That We're a Family, Ballerina Farm (all American) for maybe a different slant on it. Interestingly Ballerina Farm's lifestyle is apparently likely to be financially underwritten by their wealthy father in law who is a billionaire airline owner, so again there's a bit of smoke and mirrors going on. It's really the fact they're embracing religion that made me think of it, although I'm surprised it's Catholicism. Trad Cath is definitely a thing as well (very conservative young Catholics).
Could not be relevant at all, but I do find it fascinating where they're getting their influence from. Not at all such a thing in UK or Ireland I don't think!