Yea, if only changing all 4 tyres didn't take about 30 seconds changing the tyres might actually be a smart thing to do, but as it stands there is only one slow ass changing each wheel at a time.
Your not thinking about what pitting actually means in smaller races, if you actually thought about it's affects then maybe you'd realise there is still stratengy in doing a 1 second pitstop.
If you are running a combo where the tyres more than likely get hot towards the end, pit in the last few laps and the tyres will be that little bit cooler. Or if your happy with pitting at any point, pit when you start catching back markers or you get stuck behind someone who defends really well.