Be reasonable. I'm not trying to argue. Stop being so Agressively defensive. It makes you look guilty. At the end of the day, unless the producer of the work has given you permission to hold a permanent copy of the work, be that by general statement that their work is for stock use, an email, phone call or whatever, it's essentially stealing. Just because your browser might cache an image does not mean you are allowed to keep it. There's no real harm in it if it's purely to keep in digital form only for you as say a desktop background, but if you plan to use it in another form, be it as contributing work for an alternate piece or printing, et cetera, you should really seek agreement. But then you know that. Allegedly. at least ask for respects purposes. It doesn't cost anything to ask. I'm not going to argue this with you as it's you who looks bad here. I just think a little politeness and respect for the original artist goes a long way. If they've said you can use it then great.
