Spray matte coatings can indeed be easily scratched and chipped; I can't speak for spray gloss coatings, as I have no personal experience with them, but brush-on gloss coatings (Triple Thick, Tamiya gloss, Future floor polish, etc) can be extremely durable. The durability you'll want will ultimately depend on how you plan to store your miniatures, however. If you transport them separated in a lined box and treat them overall gently, then a less durable finish can be just fine; if you tend to toss them all in a box, you'll want something more durable to prevent them from getting banged up.
You can layer finishes; when I do miniatures, I do coat them in brush-on gloss (Triple Thick) for durability followed by a spray of matte finish (Dullcote or Purity Seal/Munitorium Varnish) to cut the shine. The minis I've treated in this manner are from a board game and stored in the game box, and so far have not chipped or shown any damage to the paint or coatings. They aren't as matte as they would be had I used only the final matte finishing spray, but they aren't glossy, either; your desired finished look may have some impact in how you choose to finish your miniatures, as well.
As an addendum, if you are using only plastic or metal miniatures, Krylon sprays are likely fine, but if you choose to purchase any "premium resin" miniatures, under no circumstances should you use Krylon on them; Krylon has been shown to behave unpredictably on polyurethane resin, ranging from "it kind of worked but didn't dry/cure well" to "it pitted/ate away at the surface where it was sprayed."