I think your numbers are off....
You MAY need a set of tires, but only if you are currently on tires that are worn out. Lake Erie is easy on tires. Most of us that race there weekly get a full season on 6 tires (1 set Left and 2 sets of rights)
There is no requirement to run Wednesday for practice. It is optional. There is also no requirement to rent a pit stall. Last I checked, pit location doesn't make a car faster, so if you don't care where you park, don't pay for a stall. The fuel is pretty reasonable, but I agree $5.75 for 93 octane (it is not road fuel though, so no-ethanol) is a tad high.
If you have a decent set of tires to start with, total cost should be about half of what you said.
This is no different than past years. After all, it is 3 days of practice/racing. That isn't cheap to support from a track/uslc perspective, and they do need to make a bit of profit or why do it?
If you really want to save money, bring a tent and camp it. The track has very nice facilities, and even have showers in the rest rooms. The weather will likely be cool, but not cold, so sleeping in a tent will likely be comfortable. Again, all about how you choose to spend your money. Hotels are nice, but they don't make you faster. There is a walmart not far from the track, so go and get some groceries, and save even more money.