I would venture to guess that 95% or more of retai

I would venture to guess that 95% or more of retail accounts are margin accounts. EVERY brokerage tries to talk people into signing up for margin accounts. There are great advantages for traders -- for instance, if you sell something, you don't have to wait for 3 days for it to clear before you can use the money to trade again. Most people don't know that there IS such a thing as a cash account. I remember setting up an account at Waterhouse years ago, and when I told the guy I didn't want a margin account, after he tried to talk me into one, he then finally and reluctantly had to go INTO A DIFFERENT ROOM to get a cash account application form.

Most people don't buy on margin. Having a margin account doesn't mean that you MUST run yourself into debt buying on margin. It just means that you CAN do that, and it makes your money available immediately instead of waiting for trades to clear.

Most people do not realize that their shares can be lent out to be shorted. In fact, an awful lot of people have HEARD of short-selling but are only dimly aware of what short-selling is. That's why mainstream media articles almost always include a brief explanation in parentheses the first time they use the term.

Schwab and some other brokerages offer to pay you when they lend out your shares to a short. They caution you that it may adversely affect share price of your investment. Fidelity does not do that - pay your, or caution you. They are not bound by law to do so -- as you say, you sign away your rights when you get a margin account with them. But, it should give you a little pause when you realize that some brokerages give you money for the use of your shares, and others do not.

If I'm going to let someone short my shares, I'd certainly like to get some of the profit from them.

And I never said it wasn't legal. But in my book, I'd rather use a brokerage that won't do that without sharing profits with me.