Money doesn't buy elegance. You can take an inexpensive sheath, add a pretty scarf, gray shoes and a wonderful bag, and it will always be elegant.
If you are buying in France, there will be scarves made in France and scarves made in other places in the world . . . India, China and so on. I try to buy those made in France but others will be bought because they are "perfect" for the recipients or "something I have always been looking for".
The reasons a scarf makes the perfect gift when travelling France are that:
1) Absolutely representative of the French look
2) Light-weight - what with airline luggage restrictions . . .
3) Takes up very little space - more luggage restrictions . . .
4) Packs easily and you can even use them to cushion fragile purchases which I don't encourage you buying.
5) Scarves don't break.
6) Suitable for everyone, both male and female.
7) Whatever you don't give away as gifts, you can keep for yourself.
Factors to consider when buying a scarf for someone else should, in the best case scenario, be specific to the person for whom you are buying. However, that will provoke you into shopping for others all the time without any consideration of yourself and worrying needlessly that you didn't pick something up for so and so.
My suggestion is to simply buy what you like when you see it and only buy scarves. Don't worry about the fabric. There are beautiful selections in cotton, acrylic, silk and cashmere at many different price points. I have purchased 100% cotton for 3Euro, acrylic for 20Euro and 100% silk for 45Euro so you can maintain your budget. Each one was beautiful in its own light. You can overbuy but don't overspend.
If possible, ask the sales associate to demonstrate how to tie the scarf. Learn it and share it. That too embellishes the gift. There are several great videos and websites demonstrating scarf tying. I like this one in particular.
One visit to Galleries Lafayette or Printemps may be sufficient to fill the entire gift order. Or you can leave it up to chance and hope that you will find artist-made unique specimens in the places you visit. Make sure you keep a journal describing the place where you bought it, whether a market,a department store, or from a crafter. The story, in fact, becomes part of the gift. This suggestion comes from an experience that I was able to laugh about later.
That experience was with chocolate. We were in Zurich and of course, I went to a Lindt shop to buy gifts. I picked up what I thought were unique to Europe - miniature milk cans, representative of the old way of storing milk, filled with Lindt chocolates. Perfect. The chocolate was encased so that it wouldn't squish and there were no luggage restrictions at that time so I did not even consider the space. I would simply buy another suitcase if needed. I returned to Canada and within the first couple of days, without thinking about chocolates, I went to the local Shoppers Drug Mart. Wouldn't you know it? There in the chocolate section were my Lindt milk cans! I carried them through Switzerland and Italy and there they were 2 km away from my home in Canada. The story embellished the gift and everyone included laughed along with me.
NO THANKS: My only "do not do" regarding scarves is that you stay away from designer knock-offs. First, although they are readily available, especially if you are in Paris, it still is illegal (perhaps not always enforced) and if you are returning to Canada with 20 fakes you may end up having to spend time explaining your motives and intentions. The possibilities are not pleasant even though the likelihood may be remote.
NOTE-WORTHY: This can be a birthday or Christmas gift buying resolution for the year, not only when you are travelling. Choose an accessory - scarves, gloves, earrings, cuffs, socks . . . whatever and be on the lookout for items in your chosen category to buy as gifts. It certainly simplifies the process. One year, I bought books, another year mittens or gloves and so on. You won't be financially overburdened when you have five birthday gifts to buy in one month or at Christmas.