A new group in Fear The Walking Dead, known as The Stalkers, are taking clothes from walkers. The season 7 premiere, "The Beacon", introduces viewers to Will – a lone wanderer who explains that this new group seems to collect clothes from the dead. Since this unusual behavior is unlike anything seen on the show before, it raises serious questions about the new group's potential motivations.
The episode primarily follows the character of Strand, while exploring the aftermath of the Texas bombing from the season 6 finale. In addition to his explanation of The Stalkers, Will offers Strand vital information, such as the whereabouts of Alicia. By the premiere's end, however, Strand kills Will, fearing that his presence will persuade Strand to revert to his benevolent side, something he fears will jeopardize everything he's built. Afterward, he installs a light he and Will took from a tower, using it as a beacon to draw in walkers as a defense against other groups. This will likely lead to a confrontation with the stalkers.
While there isn't much known about The Stalkers yet, it's easy to assume that the primary reason for taking clothes off the walkers is to find protection from the radiation and safely navigate the fallout. As shown in the premiere and likely throughout season 7, the nuclear apocalypse in Fear The Walking Dead changes Texas in drastic and detrimental ways. It makes sense that with the situation so severe, The Stalkers will resort to any means in order to find the necessary equipment needed for protection from the radiation.
In the cold open of "The Beacon," the audience sees Will's daily activities as he navigates the nuclear wasteland. What's important to note here is that Will is shown wearing a gas mask and is carrying a Geiger counter to inspect the area for deadly amounts of radiation. The Stalkers are also seen wearing gas masks when attacking Strand, Will, and the others. These tools are important when navigating nuclear fallout, so it makes sense why The Stalkers take great precedence in trying to locate them. In addition to finding these tools, they could also be using the clothes from the walkers to make protective suits to combat radiation hotspots and even zombies infected by radiation.
As mentioned before, there's still a lot left to learn about The Stalkers in Fear The Walking Dead. That being said, the best possible explanation for why they are taking clothes from walkers is that they will use them for protection in the nuclear apocalypse. With that in mind, viewers will likely have their questions answered in season 7's "Six Hours," where they seem set to have a large presence and come face to face with Morgan, Grace, and baby Morgan.