Hank the Lounge is alot of work and quite a few oohs and ahhs. But who minds the waste of time without pay eh?
Yes, but you see, I do that for myself and it costs me nothing. It's a hobby (like the house lights), but one that won't dent my wallet.
These DJs aren't doing it as a hobby or giving it away. If they were, I'd say go for it. The reality of it is that they have to get a return on all that stuff. That means their rates go up and they narrow their client base. Now, they could drop it for regular jobs or list it as an add-on, but if you give people the choice to save money, most times, they will. The only way to get a return is to use it.
The point is that you're going to spend extra time, money and effort "selling" something that is basically fluff. After you pay to acquire it, insure it, store it, maintain it, transport it, set it up and break it down, how much more dough are you going to put in your pocket? If it wasn't guaranteed to be a lot, I wouldn't feel the need to work that hard for it.
You can pimp your ride all you want, but it's the mechanics that are going to get you to your destination.
That's just me. I'm not asking (or expecting) anyone to agree. Just taking a different angle.