As I shop eBay for good buys all the time I see the new Piko, USA Trains, and other manufactures of G Scale rolling stock their prices for new stuff is pretty high. Just for a start a new Piko freight car is in the $125-$150 range, these are nothing new as they are the same as what was produced when it was LGB. Yes, you get a different paint scheme, but the cars are the same plastic that you can buy on eBay in the $40-$60 dollar range. Just makes me think are there really buyers out there that are paying these high prices for old plastic with different paint jobs. I guess for some if its what you want you will pay for it, but for me being a modeler I enjoy buying a car in the $30-$40 price range and doing a repaint and re-letter to my liking for very little monies invested. Many used cars on eBay, or wherever you find them will have metal wheels and couplers to your liking, which is $50 worth of accessories that you get for free.
The price of new equipment is crazy and it is possibly keeping people from getting into the hobby.
I went to a local department store that used to sell G a few weeks back and sure enough they still had the 4’ lengths of LGB straight track for $40 each! Years ago I remember speaking with the guy that ran the train/hobby section before he retired and I was asking about a Bachmann Lynn engine he had at $400. I ended up buying the exact same engine from Trainworld for $125.
Deals can certainly be had but you have to look around. I think that is why 90% of my RR is preowned.
I haven’t bought anything new from a dealer for a long time.
Except if they have a sale and I think it is a good price. Recently Trainworld had the Bachmann
2-6-0 for $599. If I hadn’t already had the one I wanted, I would have probably bought one.
Instead I look for used from Ebay, Etsy, etc.
And I like restoring and bashing junk, it is part of the hobby. 
Short answer is YES. The number of hobbyists continues to grow and there are so few G scale manufacturers, especially of the modern rolling stock that seems to be preferred by the younger folks (which rarely shows up on eBay). Also, I find there are far less people willing to rehab a model. 
Buying new is cost prohibitive for me. Unless its the odd piece of track or accessory, I buy used almost exclusively. I scrounge and I also use things outside of typical suppliers, being indoors gives me more leeway as to sources. For example I have used 1/35 WW2 diorama buildings for example. I build them as intact structures as opposed to having a tank parked inside it. These are often pre-damaged so they fit right into the dusty southwest almost ghost towns of my layout. They can be inexpensive and give you a wider variety then the generic Aristo, Piko or Pola structures found on 90% of layouts out there. But they are indoors only.
I wish I could find cars I need to be rehabbed. Specifically some 3 bay AML 
Buying to rehab can be a costly undertaking, that is looking for replacement parts in many cases can be very costly and in many cases, they are just not available. I really study the pics on eBay of what I’m looking to buying and would look for cars that have all the parts and would rather have some scratches that I can repair back to like new condition. As I repair and repaint just about everything I buy these days, that’s just part of the hobby for me. I try to purchase my rolling stock in the $30.00 range and shipping under $15.00. I’ve been repainting with Rustoleum X2 spray paints and make my own decals on the printer. Just having fun and adding a different dimension to the hobby.
John, Charles Ro sells many USA Trains boxcars for $35-40 brand new!
https://charlesro-com.3dcartstores.com/assets/html/g_afterxmas.html
Piko “Stuff” is not ex LGB…it’s mostly made from old Model Die Casting molds.