Can you park overnight?

I seeing overnights there

Yes

For an RV?

Im not to sure

I think so

Given the problem with homelessness and derelict RVs in western Washington, you should probably ask the manager before you do! It used to be common practice and allowed in all Walmarts, but that's changed quite a bit in the last couple years.

I was told no today and that I would be towed

Yes but if it were me, I wouldn't for the reasons mentioned by others

Yes you can, however; as homeless campers are on the rise, you should let management know where you are located. This will help them eliminate your vehicle as a potential problem.

I have seen Tv's and the occasional car in their lot late at night. Even saw them Christmas Day when the store was closed.

Most Wal-Mart's allow parking over night