Chuck or "stew" beef labeled in the super market Preliminary

So I found this simple pot roast recipe here. I have cooked this plenty of times, but for some reason lately, the 'stew' or chuck roast beef is turning out to be too fatty (as it is labeled, it looks like this left picture here:


Lately, I keep buying beef that turns out to so full of fat (even from different super markets) it is just disgusting. I normally would cook this beef in a slow cooker after briefly browning it in a cast iron skillet, and since almost no fat is rendered out, it would end up like eating a stick of butter (nothing about it tasted like beef). 

Questions seeking Seasoned Advice:
Are stew beef cuts not meant to be used in stews/pot roasts? If not then what is the ideal cut for pot roasts? Or is the super market selling bad beef?
"Stew beef" is slightly cheaper than buying a whole roast and cutting it up, because the stew beef is made up of bits and pieces that were left over after the prettier roasts had been carved.

If it's not to your taste, spring for a whole roast and cut it up yourself.

WARNING: Fat content in meat that is supposed to be cooked for a long time is a good thing. Keeps the meat from drying out. It's more efficient to simply cook the stew in advance, and then skim the rendered fat off the top, before you reheat it.