Cheap vs. Frugal, a gentler distinction

Just about every frugal blogger that I read has written at least one post on the difference between being cheap and frugal. While I very much understand and agree with the need for a distinction, I don't always agree with the way they draw the line. Generally, things that require care and discipline, such as hanging laundry or eating less meat, are considered frugal. Cheap is usually defined as an excessive desire to save money, and the examples are almost exclusively immoral or illegal, such as not tipping in a restaurant or filling a free water cup with soda. While the word cheap certainly has a negative connotation, I'm not sure I agree that everything cheap is bad.

The way I understand it, frugal means trying to use less goods and resources. Cheap means trying not to pay for goods and resources. This can, of course, mean trying to cheat someone, but I don't think it always has to.

Some cheap (but not frugal) things I do, which I don't think are immoral"

I always take a free logo pen when it's offered. I keep myself and my classroom well supplied with pens this way, and I never have to pay. I could probably stand to be more frugal with them, as they often get lost or wasted, but I don't think it's wrong to be cheap at acquiring them.

I eat the free lunch that's offered me at work. I never take more than my fair share, but I don't feel the need to bring my own gourmet lunch from home or to skip lunch entirely.

I use coupons and rebates to buy groceries. If the manufacturer wants to pay for my groceries, I will gladly accept.

I go to the bathroom right before I leave work. I figure that way I'm using someone else's water, paper, and soap. Okay, this one might be a bit silly, but I still don't think it's immoral. Now, rolling TP onto a roll in my pocketbook would be immoral.

I'm sure there are more examples, but I'm a bit fried right now. What are some things you do that are cheap and perfectly moral and legit?