It is standard protocol with timeshare tours to REQUIRE both spouses tour if married (if both spouses are actually on vacation together of course.). I own both DVC and another great TS. When we decided to tour while on vacation, one of the first things we were asked is if we were married, upon our answer of "yes", we were advised we would BOTH have to be present to get any incentives.
For a long time, DVC's larger gift card incentives, $100 Disney gift card, clearly stated in the find print that both spouses must attend to receive the incentive. DVC is the only TS I know of that kind of waffles on this. Data from TS tours clearly shows that the percentage of solo tours that buy is extremely low. How many people would make such a decision/investment without consulting their spouse? Not many. If the guest is single, no problem.