"Raise the bar at the bottom and all wages will go up"
The people at the bottom might be making more, but they won't have spending power for very long because the cost of everything will go up. This cycle will just continue forever, unless the government starts fixing prices, which never leads to a good outcome.
When fast food workers wages are raised, we might see a few dollars more for meals. When you raise the wages in every other industry, it has a cascading effect. Just look at the number of jobs between products on the store shelf and how it gets there. Delivery, trucking, packing, shipping, etc. In this one example, it would raise prices 10X.