Can We Talk About The "Purple" 4 Cent Lincoln Stamp

I am new to stamps and essentially know nothing- I do have a small hoard of stamps from 1940's-1970's. including around 30-40 of these 4 cent purple Lincoln's. Us and foreign war time stamps. Picked up a box full of envelopes with mail inside. Like going back in time!

Long story short, why are some of these stamps on ebay from .50 cents to thousands..? Few pics for reference.

Because while ebay can be a great resource for collectors it is also full of people trolling for suckers, laundering money and some are plain insane. Kind of like the NYC subway.

Since there is no filter for idiots on ebay, anyone can ask anything. And the web attracts idiots. Just search for "juju" on this forum and you will get an idea of what is happening.

https://goscf.com/t/84411

I figured so much. Informative though thank you. The juju forum is hilarious thanks for sharing that.

The 4 cent Lincoln stamp was current during the 4 cent letter rate and was printed in sheet, booklet, and coil format in immense numbers as the workhorse design of its era. It is extremely common and essentially worthless as a plain used stamp.
That said, as you are discovering, the "postal history" aspect of the cancels (some of the military APO cancels can be uncommon) and the enclosed letters can be very interesting as "social history" and can have some monetary value.
Last year I found 3 letters my parents sent to each other a few months before they got married. Interesting at some level, but they should have burned them! LOL.