I've never had a weekend car, but I've had "rainy day" appliances to use when it rains or when I need to shuttle more than one. But I never had a car only to be used on the weekends or special occasions, I've just had other vehicles for practical reasons...or because I didn't feel like cleaning my fun car so I'd drive the appliance if I expected rain (or ice, or snow, etc.).
But now, with multiple ride-sharing apps which don't seem to be going anywhere and the advent of Turo, I'm no longer keeping a car simply for practicality. It'll be cheaper for me to simply rent a car (or use Uber/Lyft) when I need to drive multiple people around, or if a major storm is coming. Owning an SUV or sedan 365 days/year just to have it for when I need to move or haul people is no longer making fiscal sense with car payments, insurance fees, increased emissions regulations, etc.
And now I just drive my fun cars in the rain and clean them up afterward.
So, I'm going all in...only fun cars for me from here on out. I'll rent the proverbial appliance when I need it (or I'll borrow from family or friends).