LEDs are 4-5 times more efficient than incandescent bulbs, not 7 times. Honest 100W equivalent will draw more than 15W. Though technology is improving, maybe recent expensive LEDs can do.
With a run off the mill ebay LED, it's either less than 100W equivalent brightness, or it draws more than 15W. I assume the OP didn't actually measure lumens or wattage, and the numbers are taken from the seller's blurb.
Agreed on directional nature of LED. They are good for ceiling fixtures or areas like kitchen counter. Directional light and/or cooler color with better contrast makes impression that LED drawing 15W is "brighter" than a regular bulb drawing 60W, while they in fact emit same total amount of lumens. 15W is still better than 60W, even if all this energy was wasted in heat.