The Walmart on the Gilford/Laconia border has a big array of boat ropes. anchors, gas lines and tanks, paddles, pfd's, cleats, 2-stroke & 4-stroke oil, outboard oil filters, fish-finders, cleaner, wax, lights, ...... various do-it-yourself boat items. It has a much larger boat maintenance/install items than most other Walmarts because the area is big with boaters.
Your boat will not know the difference between a bowline that came from Shep Browns or a bowline that came from Walmart because it is the exact same item, except for the price. Ditto that for outboard oil and many other items .....