Yes, but there was still fraud. You didn't send your money away to just any random ad you ran across. Sears was VERY well known. And if you didn't know the company or its reputation, you likely wouldn't send your money away to buy something without at _least_ hearing a positive experience from someone you know and trust.

MITS was not unknown, but they were not a household name. And any microcomputer at that time was quite an expensive toy. Costing an amount that a lot of people could not really afford to just lose.