DB,
For the cheap parking places, check craigslist for your target area. I've
seen decent neighborhood dockage offered in my area since money has been
tight. Usually there are caveats about limiting overnight stays, amount of
time on boat, power, water, etc. All makes sense since these are usually
docks behind a privately owned home. Don't know if anyone is doing it for
a
few days at a time.
As for the moorings, you'll see more and more of this happening as cities
crack down on anchoring outside of designated areas.
In our area, cheap mooring would have a waiting list with the locals and
unless a number were reserved for cruisers, they'd still be out of luck.
About people spending money, it more than likely wouldn't be much unless
they happen to break down and need a service professional. I stock my boat
before I go and buy the minimum along the way. If we overnight on a dock,
we'll hit a close restaurant for dinner.

I think cruisers would tend to patronize local restaurants on days
when locals do not because they are cruising on weekdays. Such
cruisers are either beginning or ending a portion of their cruise and
will celebrate at a restaurant.
Notice I said these moorings would have a 2 week limit so locals are
not likely to use em.

--------
You're right, a lot of people make use of local restaurants but I'm guessing
not enough for the city gov't to set anything aside for them. I get the
impression that most waterfront cities are way more interested in keeping
the high dollar tax payers happy than looking after this relatively lower
end tourist market.
I've seen some cruisers anchor out off marinas and wait until the marina
closes for the day and then dinghy in to make use of showers, laundry, etc.
that were put there for the people that pay for slips and the use of the
facilities. Too many to argue the allegation that sailboaters are cheap. I'm
cheap but I still have some standards and they include not trespassing on
private property to take something I didn't pay for.

I agree, transient morrings would be great.
When we were members of Cocoa Beach YC (blue collar YC) we had 2 or 3 slips
dedicated to boats in transit and the dockmaster would allow transients to
short term in slips whose normal tennets were cruising. Some transients
abused (and were allowed to) the privilege but mostly it worked well and the
club was able to help out boaters on the move. They may still do this but I
quit a couple years ago and haven't had a boat there for 6 years so lost
track of what is going on.
Hope your multi-legged trip goes well, sounds like your off to a good start.