I’ll remind you that sailing ships big enough for piracy very much cost more than a house. If nothing else, they’re way bigger than a house, and literally house dozens of crew for long stretches of time. A huge amount of modern capitalism was invented exactly because ships were so expensive and risky (insurance, large scale banking, corporations, risk assessments, time value of money etc)

But yeah. Valuable space freight passing through areas of space with complicated conditions with many safe harbours for the pirates, for one reason or another. Political (government doesn’t care that they pirate against those other guys) geographical (countless small islands/asteroids makes searching for them futile), or otherwise