I'm not sure where your confusion lies. OP likes having two rows of F to their own party because it creates the allure of safety having no one seated behind them. While it's wonderful that makes them feel safer, the reality is that it's silly for DL to be sending out so many empty seats that could just as easily be filled with other paying customers if they required people of the same household to sit next to one another. Yes, I'm sure most would agree they'd rather not be seated next to a stranger at this point (or realistically at any point) but I think extending that concern to those seated behind you is a bit too much when you're choosing to fly on a commercial aircraft.

I'm by no stretch a DL apologist and I'm rarely the first one to go to the defense of any airline, however in this case DL is justified in trying to sell those additional seats IMO.