It is possible to cover up your stretch marks by going to a spray tan salon to obtain a good airbrush tan that is evenly applied on the skin. Airbrush tanning, unlike sun bathing or other methods of tanning will produce a very even, dark colour on the skin. This will darken the colour of the stretch marks thereby enabling it to blend together with the rest of the skin. Your beauty technician should be able to blend the colour of your stretch mark with that of your skin. This is why you cannot do this at home on your own, you need the services of a professional technician to obtain a good and quality tan.
If you allow unprofessional persons to apply it for you, the beauty technician can apply too much color over the stretch marks in a bid to cover it up. This can further make the marks very visible and many people will notice it immediately.
In order for you to maintain properly covered stretch marks, you will need to reapply your tan solution immediately you notice it fading away. If you allow your tan to fade before your reapply, the stretch marks will be very visible again.
So, yes, stretch marks can be covered with a spray tan provided you maintain it.