Here in Canada, Home Depot is not too bad yet but getting worse. There used to be 15 cashouts in the local store, they are down to two regular and one for lumber. They used to stock an suppliers entire line down to the last little item, now it is only the big sellers. They squeezed in appliances and dropped hardwood veneer plywoods and only carry some thicknesses of plywood, mdf and other sheet goods. If you want other thicknesses, go elsewhere.
When I can, I go to the local Revy Store, unfortunately it is very small but they can pack in almost as much merchandise as Home Depot, except building materials which are outside and sheet goods which they don't have much room for. They have cashiers and floor help and a bigger variety of many items.
We used to have 5 lumberyards and 3 hardware stores, now we are down to Revy, and Home Depot with some Canadian Tires which don't carry lumber and building supplies. The one good lumberyard closed its local store and moved to its rural store where it still is if you want a 30 mile round trip.