I didn't find the lines to get into shops too bad. There were only 3 times we had an actual line to stand in.
One was for World of Disney at Disney Springs. That said, the line moved the entire time and I think they were just staggering entry and not really keeping the #s down.
Another was for the store outside the Haunted Mansion. We waited maybe 5-10 minutes to get in there. It's a very small store so it makes sense we had to wait.
The last were for the stores in Galaxy's Edge. I'm counting this as one line. To go to the Marketplace shops, you must stand in a line to get into the Marketplace. From there, you need to stand in a line to go into the actual 'shop' you want. They only let one family at a time in a shop. That said, it's easy to see what is in each of those little shops before you get in line so that you do not stand in a line for a shop that has nothing you want.