I think a modest snood (covering all hair) IS more tzniusding than the type of sheitel you describe. So although in these type of communities – it is understood and accepted that a snood is more “casual” and not dressed up as a sheitel… SO WHAT!. Obviously whoever is wearing a snood, is currently in the more “casual, not dressed up” mode. What a HUGE chutzpah for anyone to impose their “mode/mood” of dressing on someone else. Not to mention that there are many pious women (usually from Israel) who prefer NOT to wear anything else BUT a snood for tznius reasons…
(The debate if a snood or sheitel is more tznius – is a whole other thing. I personally believe it is easier not to risk showing any hair with a sheitel than a snood…thus, I prefer wearing a sheitel when out and about.)