Yes, because streptokinase is much easier to produce. rec.tPA needs those precious cell-lines which necessitates lots of money and expertise to develop and are guarded in high security rooms with bullet proof doors at Western pharmaceutical companies
. I do not know the prices right now but till a couple of years ago, tenecteplase for instance was selling at 10 thousand dollars per injection. Anyways, if mechanical intervention is available, it does the job as well as tPA. Basically rect.PA is good for smaller hospitals, which do not have mechanical intervention or for ambulance crews to administer it in the field (time is of essence to rescue as much of cardiac tissue as possible).
We have Désiré Collen, Diane Pennica and California's Genentech to thank for rec.tPA.