Fairly common occurrence and tbh it's not limited to the Zeds. Any performance related car will always attract attention from the "wannabe racers".
Used to happen to me in the Zed, happened to me in all my previous cars (EP3 CTR, JDM Impreza, ST24, VR6 etc) and heck I get it fairly regularly still these days in my CTR.
That's why really a good sleeper car is the best to own as you have all the fun of a powerful engine when you want it but 99% of the time people won't bother to try & race you on the roads as your car just looks slow/standard or lacking in power.