Yes, they dismount the tires from the rims then slice them open on both sidewalls around the entire circumference of the tire.
Then they trim about 1/2 to 3/4 of an inch off the tire side (depends on how much they rub), not the bead side (rim side) because of the ‘steel belts’ it gets harder to trim and is more dangerous.
They test fit the tires back to the rim so that they are sure they removed an even 1/2 to 3/4 completely around, if not even you will get a ‘vibration’ After they are positive the tires are even they dismount again, line everything up and put them in a preheated 350* oven to ‘melt’ everything back together. If the tech is sloppy the info molded into the tire will not match so keep an eye on them.
The whole process is fairly quick, especially with a knowledgeable technician, and he should be out in an hour max, plus its a free service at most tire shops.
The only thing they charge for is the evacuation and recovery of the air in the tires, cost varies by state but generally about 10-15 cents per pound. You’ll want to make sure you get ‘your air’ back.... you already paid for it and its specific to your tires.... dont want someone else’s air contaminating yours and throwing your wheels off balance.
Not a full explanation but hopefully I explained it well enough... good luck tire shopping