Thief stealing wheels

If he got both wheels off I assume you locked the frame only to the stand?
Unfortunately you've already drawn attention to your bike doing that particularly where you are locking up.

If rear wheel was secured through the frame he probably wouldn't have bothered for just a front wheel and looked for the next unsecure wheelset.

You have to at least make your bike a slight PITA to deal with to prevent an opportunist drive-by like that.

Good point,
in this case I had to lock two bicycles with one lock,
but I will remember your advice for the next time.