The WTS tends to just kind of gloss over this point - just who were Paul and Priscilla and Aquila selling those tents to?
It's not like there were guys getting 2 weeks paid vacation and taking the family on a camping trip to a national park. A subsistence farmer or fisherman of workman would have no need for, let alone could afford, a tent.
Pretty much the only market for tents would be the military.
Today, of course, if you work for a defense contractor supplying material to the military, you are expected to quit your job, under the threat of being disfellowshipped / self-disassociated or "non-neutral activity".