

Paying a portion later means more cash can flow through the business and provide utility today. Your post implies that every business operating this way is effectively insolvent without access to credit, but even if your employer has the money to pay for the raw materials today, it generally isn’t in their best interest to do so
Quality won’t increase relative to official methods because it’s already more or less at parity with them. If the file you watch is tagged as a WEB-DL, in most cases it’s identical to the file you’d be streaming via official methods in terms of quality. It’s just remuxed into an open container format like .mkv (the video and audio streams are losslessly copied into a file format which can be shared)