They didn't intern the jews. They interned Communists, whom were constantly causing mass chaos on the streets. Think antifa in portland and times it by 100x and never stopping. It just so happened that so many jews were communists (and likewise so many of the antifa arrested have been jews). Still, many jews continued to live their normal lives in Germany, in spite of the fact that 'jewry' had literally declared war on Germany and were telling all jews to sabotage germany within and without. I personally would've exported every last one of them at that stage, but Hitler didn't. He made some effort to get as many to Israel as possible, but i guess the logistics were hard to manage.

As the war was going on they still didn't intern all the jews, despite the sabotage now ramping up to serious effects. Again, putting them all in camps was a logistical nightmare, so they put all the jews in certain districts of the city. This STILL didn't work, the jews still caused havoc in germany blowing up supplies, assasinating people, etc. So eventually they put them all in camps. Meanwhile America put the japs all in camps just as a precaution when they hadn't even done anything yet.