Really, no. But we are both EXP and that's just the way we do things. She's gonna take all the same trips (neither of us travels alone), so getting to 97% of EXP just seems wrong. Making it work for both of us is just what we do as there's minimal incremental cost. Same with out BA silver status for AA lounge access in the US.
Cheers.
Since you travel together, why not just book the car rentals in her name? (As her spouse, you should be able to drive the rental at no additional cost with Avis.)
Or does your employment give you a very favorable rental rate for which your wife is ineligible?