I have never been Thrift shopping in any other cities, but I can definitely agree that doing so here in SoCal is *brutal* beyond comprehension. The competition is practically laughable. There are, indeed, people who go daily -- thanks to the unemployment rate, it has become their full time job to buy and resell what they find. This has always been the case, but I believe because of the bad economy it's happening even more now. I have seen Thrift Stores where people literally hang out there ALL day/EVERY day. Also, I believe a lot of people who used to donate items are now selling things themselves on eBay or CL.
SO, I basically go expecting to find *nothing.* More often than not, that is exactly what happens. Luckily, vacuums are not the only things that interest me. I also have a fondness for vintage speakers/stereo equipment. I usually find things that are fascinating to look at (even though I'd never buy them). But yes, there are times when I go and there ain't squat. But I still keep going back...and eventually find something (like the recent Tristar CXL I posted about). I only go on weekends, so I believe a lot of what I find are things that the usual vultures didn't want. I consider myself very privileged to have found what I already own.
In our area, I think the Salvation Army has the worst selection. They've resorted to 40/50% off sales EVERY weekend..and they never used to do that. I think they are in trouble (here at least). Goodwill is always hit or miss. The Council Thrift Stores seem to get fairly good stuff. Out of the Closet also does, but they are VERY hit or miss. And of course everything I've just stated changes on a daily basis. It's pretty much always about LUCK.
If you've only gone a few times and saw nothing...you have to go more than that. It pretty much has to be an obsession I think. Patience, perseverance, a good sense of humor and a LOT of luck are all required.
