I was to my local (German village) Christmas market, and it was nice. Alle the stalls run by local nonprofits or small businesses, resulting in reasonable prices. You'd have to forcibly drag me if you wanted me to go to a fully commercial big city Christmas market with its outrageously inflated prices and silly paranoid security theater.
Unfortunately you won't find Christmas markets like that in the touristy places and big cities, because they'll typically charge a shitload of rent for a spot to put up a stall, so only commercial vendors with rip-off prices can afford to take part.
In small towns and villages, the organisers will possibly ask for a small charge for the consumables (water, electricity) your stall uses, but rarely for the space, and if so, then very little. Due to the short duration of those small Christmas markets, they are unattractive for the typical commercial fairground vendors, so you'll only find stalls run by the local non-profits and small businesses.
Ours had stalls offering the following:
Hot alcoholic drinks (run by one of our two sports clubs)
Hot soups and stews (run by the other sports club)
Hot (alcoholic and non-alcoholic) drinks (run by a local pub)
Fish and seafood (run by the anglers' club)
Honey and beeswax candles (run by a local beekeeper)
Advent wreaths and the like (run by a local flower shop)
Christmas decorations made of wood (run by a dude who does some woodworking as a side business)
Homemade bird feeders and nesting boxes (run by the bird protection association)
Waffles, hot mead, coffee, and various Christmas decorations (run by the church)
Coffee and cake (run by a local farmer who does some baking on the side)
There were a few more, but I can't recall precisely what they sold, I totally blame the exquisite selection of vendors of hot alcoholic beverages for that.