Seriously, there is absolutely nothing wrong with owning 2, 3 or 10 cars, but for most people whose name does not end in "Leno", we need to have a plan to justify it. I have two very distinctively different Challengers, both exactly what I want, nothing alike, if I had to get rid of one, I'm not sure which I'd part with.
In your case, the cars are very similar, so the only reasons to keep both are:
1. You have one to modify and race, the other to take the kids to school.
2. You have a spare so when you burn one out at 150kmi, you have a replacement.
3. You truly believe you can make money by hanging on to the 2nd car.
4. Add your own thoughts.
One of the greatest things about our country, is that we are not "needs" based, we are still (mostly) free and entitled to the pursuit of happiness, you just need to figure out if owning the extra car adds to or interferes with the happiness goal, and only you can determine that.
Have fun, be logical, maximize happiness!