LOL!! So enjoyed reading your prose, and every paragraph rang sooo true to personal experience.

The only suggestion I can offer is the possibility of enlisting a mobile vet (assuming there is one in your area) to make a house call next time routine stuff is needed . . . of course, given Ritz's keen memory, that blindsided move would only work ONCE with her. But at least it would throw her a curve and possibly eliminate utter panic the next time her carrier becomes visible. You could also try putting her in the carrier and taking her for a drive. Upon returning home, lavish her with affection/playtime/treats; whichever is her favorite! Consider it "Puttin' on the Ritz"