No! Low prices are NOT good for people. And that's the point you are missing. The price of an item needs to account for raw materials, manufacturing, regulatory compliance, corporate taxes, shipping, and the salaries/benefits of every individual involved along the way, from the picker in the field to the factory worker to the delivery truck driver. If at ANY point along that way someone pays less, then someone else has to make up that deficit. For example: Senator Buttcheese gets Widget Factory to open their new factory in Senator Buttcheese's state capital of Sandusky. This is a big win for Sandusky, because there will be 500 jobs to fill at the factory. But to get Widget Factory to move to Sandusky, the Senator agrees to give them a 10-year break on taxes. STOP. Read that again: "...a 10-year break on taxes." Widget Factory can now lower their prices BECAUSE THEY ARE NOT PAYING TAXES. So retailers start buying Widget Factory widgets, instead of the old ACME Widgets, because Widget Factory's are cheaper, and paying less for products increases the profits for the retailer. 10 years later. The roads in Sandusky are destroyed. Potholes EVERYWHERE. Especially around the Widget Factory, which is booming and now employs 1000 Sanduskyites. A local ballot measure for road repair gets passed, adding a $1.00 surcharge to all automobile licenses issued in Sandusky. Now the 1000 workers at Widget Factory are paying increased taxes to repair the roads that have been destroyed by Widget Factory trucks, because Widget Factory is NOT paying into that fund, because of their tax break from Senator Buttcheese, who died several years ago. Dippy McShithead now runs for Senator Buttcheese's seat, on a platform of "Cutting Taxes!" to ease the tax burden on poor Sanduskyites. (And you have the last 30 years of the Republican Party, in a nutshell: Create a problem, blame someone else, and claim tax cuts will fix it.) So no, low prices are NOT a good thing. For anyone. They are short-sighted, and wind up hurting people in the long run. I said: "Step 2: Offer prices too low for any local competitor to meet."
You said: "Do you agree that this one, specific effect, lower prices when Walmart comes to town, is good for the locals?"